Merge remote-tracking branch 'origin/master' into source-aware-reprinter

2024-11-28 01:47:01 +03:00 · 2018-08-20 10:17:38 -07:00 · 2018-08-20 10:17:38 -07:00 · 3c53862e19
commit 3c53862e19
parent 4e5983c5e0 46eace3c50
25 changed files with 1282 additions and 1057 deletions
--- a/.licenses/semantic/cabal/haskeline.txt
+++ b/.licenses/semantic/cabal/haskeline.txt
@ -0,0 +1,31 @@
+---
+type: cabal
+name: haskeline
+version: 0.7.4.2
+summary: A command-line interface for user input, written in Haskell.
+homepage: https://github.com/judah/haskeline
+license: bsd-2-clause
+---
+Copyright 2007-2009, Judah Jacobson.
+All Rights Reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+- Redistribution of source code must retain the above copyright notice,
+this list of conditions and the following disclaimer.
+
+- Redistribution in binary form must reproduce the above copyright notice,
+this list of conditions and the following disclaimer in the documentation
+and/or other materials provided with the distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS "AS IS" AND ANY
+EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR THE CONTRIBUTORS BE LIABLE
+FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
+USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
--- a/bench/Main.hs
+++ b/bench/Main.hs
@ -12,11 +12,11 @@ import           Semantic.Task (withOptions)
 import           Semantic.Util hiding (evalRubyProject, evalPythonProject, evaluateProject)

 -- Duplicating this stuff from Util to shut off the logging
-evalRubyProject   = justEvaluating <=< evaluateProject (Proxy :: Proxy 'Language.Ruby)   rubyParser   Language.Ruby
-evalPythonProject = justEvaluating <=< evaluateProject (Proxy :: Proxy 'Language.Python) pythonParser Language.Python
+evalRubyProject       = justEvaluating <=< evaluateProject (Proxy :: Proxy 'Language.Ruby)       rubyParser
+evalPythonProject     = justEvaluating <=< evaluateProject (Proxy :: Proxy 'Language.Python)     pythonParser

-evaluateProject proxy parser lang paths = withOptions defaultOptions $ \ config logger statter ->
-  evaluateProject' (TaskConfig config logger statter) proxy parser lang paths
+evaluateProject proxy parser paths = withOptions defaultOptions $ \ config logger statter ->
+  evaluateProject' (TaskConfig config logger statter) proxy parser paths

 -- We use `fmap show` to ensure that all the parts of the result of evaluation are
 -- evaluated themselves. While an NFData instance is the most morally correct way
@ -30,10 +30,10 @@ rbEval :: FilePath -> Benchmarkable
 rbEval p = whnfIO . fmap show . evalRubyProject $ ["bench/bench-fixtures/ruby/" <> p]

 pyCall :: FilePath -> Benchmarkable
-pyCall p = whnfIO $ callGraphProject pythonParser (Proxy @'Language.Python) Language.Python defaultOptions ["bench/bench-fixtures/python/" <> p]
+pyCall p = whnfIO $ callGraphProject pythonParser (Proxy @'Language.Python) defaultOptions ["bench/bench-fixtures/python/" <> p]

 rbCall :: FilePath -> Benchmarkable
-rbCall p = whnfIO $ callGraphProject rubyParser (Proxy @'Language.Ruby) Language.Ruby defaultOptions ["bench/bench-fixtures/ruby/" <> p]
+rbCall p = whnfIO $ callGraphProject rubyParser (Proxy @'Language.Ruby) defaultOptions ["bench/bench-fixtures/ruby/" <> p]

 main :: IO ()
 main = defaultMain
--- a/proto/python-diffs.proto
+++ b/proto/python-diffs.proto
@ -30,25 +30,6 @@ message PythonDiff {
  }
 }

-message QualifiedName {
-  oneof sum {
-    QualifiedName qualifiedName = 1;
-    RelativeQualifiedName relativeQualifiedName = 2;
-  }
-  message QualifiedName {
-    repeated string paths = 1;
-  }
-  message RelativeQualifiedName {
-    string path = 1;
-    QualifiedName maybeQualifiedName = 2;
-  }
-}
-
-message Alias {
-  bytes aliasValue = 1;
-  bytes aliasName = 2;
-}
-
 message PythonSyntax {
  oneof syntax {
    Comment comment = 1;
@ -158,12 +139,6 @@ message Function {
  PythonDiff functionBody = 4;
 }

-message Variable {
-  PythonDiff variableName = 1;
-  PythonDiff variableType = 2;
-  PythonDiff variableValue = 3;
-}
-
 message Plus {
  PythonDiff lhs = 1;
  PythonDiff rhs = 2;
@ -361,6 +336,26 @@ message Tuple {
  repeated PythonDiff tupleContents = 1;
 }

+message Ellipsis { }
+
+message FutureImport {
+  repeated Alias futureImportSymbols = 1;
+}
+
+message Import {
+  QualifiedName importFrom = 1;
+  repeated Alias importSymbols = 2;
+}
+
+message QualifiedImport {
+  repeated string qualifiedImportFrom = 1;
+}
+
+message QualifiedAliasedImport {
+  QualifiedName qualifiedAliasedImportFrom = 1;
+  PythonDiff qualifiedAliasedImportAlias = 2;
+}
+
 message Redirect {
  PythonDiff lhs = 1;
  PythonDiff rhs = 2;
@ -442,26 +437,6 @@ message Yield {
  PythonDiff value = 1;
 }

-message Ellipsis { }
-
-message Import {
-  QualifiedName importFrom = 1;
-  repeated Alias importSymbols = 2;
-}
-
-message FutureImport {
-  repeated Alias futureImportSymbols = 1;
-}
-
-message QualifiedImport {
-  repeated string qualifiedImportFrom = 1;
-}
-
-message QualifiedAliasedImport {
-  QualifiedName qualifiedAliasedImportFrom = 1;
-  PythonDiff qualifiedAliasedImportAlias = 2;
-}
-
 message Context {
  repeated PythonDiff contextTerms = 1;
  PythonDiff contextSubject = 2;
@ -488,3 +463,22 @@ message Annotation {
 message List {
  repeated PythonDiff listContent = 1;
 }
+
+message QualifiedName {
+  oneof sum {
+    QualifiedName qualifiedName = 1;
+    RelativeQualifiedName relativeQualifiedName = 2;
+  }
+  message QualifiedName {
+    repeated string paths = 1;
+  }
+  message RelativeQualifiedName {
+    string path = 1;
+    QualifiedName maybeQualifiedName = 2;
+  }
+}
+
+message Alias {
+  bytes aliasValue = 1;
+  bytes aliasName = 2;
+}
--- a/proto/python-terms.proto
+++ b/proto/python-terms.proto
@ -12,25 +12,6 @@ message PythonTerm {
  PythonSyntax syntax = 1;
 }

-message QualifiedName {
-  oneof sum {
-    QualifiedName qualifiedName = 1;
-    RelativeQualifiedName relativeQualifiedName = 2;
-  }
-  message QualifiedName {
-    repeated string paths = 1;
-  }
-  message RelativeQualifiedName {
-    string path = 1;
-    QualifiedName maybeQualifiedName = 2;
-  }
-}
-
-message Alias {
-  bytes aliasValue = 1;
-  bytes aliasName = 2;
-}
-
 message PythonSyntax {
  oneof syntax {
    Comment comment = 1;
@ -337,6 +318,26 @@ message Tuple {
  repeated PythonTerm tupleContents = 1;
 }

+message Ellipsis { }
+
+message FutureImport {
+  repeated Alias futureImportSymbols = 1;
+}
+
+message Import {
+  QualifiedName importFrom = 1;
+  repeated Alias importSymbols = 2;
+}
+
+message QualifiedImport {
+  repeated string qualifiedImportFrom = 1;
+}
+
+message QualifiedAliasedImport {
+  QualifiedName qualifiedAliasedImportFrom = 1;
+  PythonTerm qualifiedAliasedImportAlias = 2;
+}
+
 message Redirect {
  PythonTerm lhs = 1;
  PythonTerm rhs = 2;
@ -418,26 +419,6 @@ message Yield {
  PythonTerm value = 1;
 }

-message Ellipsis { }
-
-message Import {
-  QualifiedName importFrom = 1;
-  repeated Alias importSymbols = 2;
-}
-
-message FutureImport {
-  repeated Alias futureImportSymbols = 1;
-}
-
-message QualifiedImport {
-  repeated string qualifiedImportFrom = 1;
-}
-
-message QualifiedAliasedImport {
-  QualifiedName qualifiedAliasedImportFrom = 1;
-  PythonTerm qualifiedAliasedImportAlias = 2;
-}
-
 message Context {
  repeated PythonTerm contextTerms = 1;
  PythonTerm contextSubject = 2;
@ -464,3 +445,22 @@ message Annotation {
 message List {
  repeated PythonTerm listContent = 1;
 }
+
+message QualifiedName {
+  oneof sum {
+    QualifiedName qualifiedName = 1;
+    RelativeQualifiedName relativeQualifiedName = 2;
+  }
+  message QualifiedName {
+    repeated string paths = 1;
+  }
+  message RelativeQualifiedName {
+    string path = 1;
+    QualifiedName maybeQualifiedName = 2;
+  }
+}
+
+message Alias {
+  bytes aliasValue = 1;
+  bytes aliasName = 2;
+}
--- a/proto/ruby-diffs.proto
+++ b/proto/ruby-diffs.proto
@ -30,391 +30,6 @@ message RubyDiff {
  }
 }

-message Comment {
-  string commentContent = 1;
-}
-
-message Function {
-  repeated RubyDiff functionContext = 1;
-  RubyDiff functionName = 2;
-  repeated RubyDiff functionParameters = 3;
-  RubyDiff functionBody = 4;
-}
-
-message Method {
-  repeated RubyDiff methodContext = 1;
-  RubyDiff methodReceiver = 2;
-  RubyDiff methodName = 3;
-  repeated RubyDiff methodParameters = 4;
-  RubyDiff methodBody = 5;
-}
-
-message File { }
-
-message Line { }
-
-message Error {
-  repeated ErrorSite errorCallStack = 1;
-  repeated string errorExpected = 2;
-  string errorActual = 3;
-  repeated RubyDiff errorChildren = 4;
-}
-
-message And {
-  RubyDiff lhs = 1;
-  RubyDiff rhs = 2;
-}
-
-message BAnd {
-  RubyDiff left = 1;
-  RubyDiff right = 2;
-}
-
-message BOr {
-  RubyDiff left = 1;
-  RubyDiff right = 2;
-}
-
-message BXOr {
-  RubyDiff left = 1;
-  RubyDiff right = 2;
-}
-
-message Call {
-  repeated RubyDiff callContext = 1;
-  RubyDiff callFunction = 2;
-  repeated RubyDiff callParams = 3;
-  RubyDiff callBlock = 4;
-}
-
-message Comparison {
-  RubyDiff lhs = 1;
-  RubyDiff rhs = 2;
-}
-
-message Complement {
-  RubyDiff value = 1;
-}
-
-message DividedBy {
-  RubyDiff lhs = 1;
-  RubyDiff rhs = 2;
-}
-
-message Enumeration {
-  RubyDiff enumerationStart = 1;
-  RubyDiff enumerationEnd = 2;
-  RubyDiff enumerationStep = 3;
-}
-
-message Equal {
-  RubyDiff lhs = 1;
-  RubyDiff rhs = 2;
-}
-
-message FloorDivision {
-  RubyDiff lhs = 1;
-  RubyDiff rhs = 2;
-}
-
-message GreaterThan {
-  RubyDiff lhs = 1;
-  RubyDiff rhs = 2;
-}
-
-message GreaterThanEqual {
-  RubyDiff lhs = 1;
-  RubyDiff rhs = 2;
-}
-
-message LShift {
-  RubyDiff left = 1;
-  RubyDiff right = 2;
-}
-
-message LessThan {
-  RubyDiff lhs = 1;
-  RubyDiff rhs = 2;
-}
-
-message LessThanEqual {
-  RubyDiff lhs = 1;
-  RubyDiff rhs = 2;
-}
-
-message Matches {
-  RubyDiff lhs = 1;
-  RubyDiff rhs = 2;
-}
-
-message Member {
-  RubyDiff lhs = 1;
-  RubyDiff rhs = 2;
-}
-
-message MemberAccess {
-  RubyDiff lhs = 1;
-  bytes rhs = 2;
-}
-
-message Minus {
-  RubyDiff lhs = 1;
-  RubyDiff rhs = 2;
-}
-
-message Modulo {
-  RubyDiff lhs = 1;
-  RubyDiff rhs = 2;
-}
-
-message Negate {
-  RubyDiff value = 1;
-}
-
-message Not {
-  RubyDiff value = 1;
-}
-
-message NotMatches {
-  RubyDiff lhs = 1;
-  RubyDiff rhs = 2;
-}
-
-message Or {
-  RubyDiff lhs = 1;
-  RubyDiff rhs = 2;
-}
-
-message Plus {
-  RubyDiff lhs = 1;
-  RubyDiff rhs = 2;
-}
-
-message Power {
-  RubyDiff lhs = 1;
-  RubyDiff rhs = 2;
-}
-
-message RShift {
-  RubyDiff left = 1;
-  RubyDiff right = 2;
-}
-
-message ScopeResolution {
-  repeated RubyDiff scopes = 1;
-}
-
-message StrictEqual {
-  RubyDiff lhs = 1;
-  RubyDiff rhs = 2;
-}
-
-message Subscript {
-  RubyDiff lhs = 1;
-  repeated RubyDiff rhs = 2;
-}
-
-message Times {
-  RubyDiff lhs = 1;
-  RubyDiff rhs = 2;
-}
-
-message This { }
-
-message XOr {
-  RubyDiff lhs = 1;
-  RubyDiff rhs = 2;
-}
-
-message Array {
-  repeated RubyDiff arrayElements = 1;
-}
-
-message Boolean {
-  bool booleanContent = 1;
-}
-
-message Character {
-  string characterContent = 1;
-}
-
-message Complex {
-  string value = 1;
-}
-
-message EscapeSequence {
-  string value = 1;
-}
-
-message Float {
-  string floatContent = 1;
-}
-
-message Hash {
-  repeated RubyDiff hashElements = 1;
-}
-
-message Integer {
-  string integerContent = 1;
-}
-
-message InterpolationElement {
-  RubyDiff interpolationBody = 1;
-}
-
-message KeyValue {
-  RubyDiff key = 1;
-  RubyDiff value = 2;
-}
-
-message Null { }
-
-message Rational {
-  string value = 1;
-}
-
-message Regex {
-  string regexContent = 1;
-}
-
-message String {
-  repeated RubyDiff stringElements = 1;
-}
-
-message Symbol {
-  repeated RubyDiff symbolElements = 1;
-}
-
-message SymbolElement {
-  string symbolContent = 1;
-}
-
-message TextElement {
-  string textElementContent = 1;
-}
-
-message Class {
-  RubyDiff classIdentifier = 1;
-  repeated RubyDiff classSuperClass = 2;
-  RubyDiff classBody = 3;
-}
-
-message Load {
-  RubyDiff loadPath = 1;
-  repeated RubyDiff loadWrap = 2;
-}
-
-message LowPrecedenceAnd {
-  RubyDiff lhs = 1;
-  RubyDiff rhs = 2;
-}
-
-message LowPrecedenceOr {
-  RubyDiff lhs = 1;
-  RubyDiff rhs = 2;
-}
-
-message Module {
-  RubyDiff moduleIdentifier = 1;
-  repeated RubyDiff moduleStatements = 2;
-}
-
-message Require {
-  bool requireRelative = 1;
-  RubyDiff requirePath = 2;
-}
-
-message Send {
-  repeated RubyDiff sendReceiver = 1;
-  repeated RubyDiff sendSelector = 2;
-  repeated RubyDiff sendArgs = 3;
-  repeated RubyDiff sendBlock = 4;
-}
-
-message Assignment {
-  repeated RubyDiff assignmentContext = 1;
-  RubyDiff assignmentTarget = 2;
-  RubyDiff assignmentValue = 3;
-}
-
-message Break {
-  RubyDiff value = 1;
-}
-
-message Catch {
-  RubyDiff catchException = 1;
-  RubyDiff catchBody = 2;
-}
-
-message Continue {
-  RubyDiff value = 1;
-}
-
-message Else {
-  RubyDiff elseCondition = 1;
-  RubyDiff elseBody = 2;
-}
-
-message Finally {
-  RubyDiff value = 1;
-}
-
-message ForEach {
-  RubyDiff forEachBinding = 1;
-  RubyDiff forEachSubject = 2;
-  RubyDiff forEachBody = 3;
-}
-
-message If {
-  RubyDiff ifCondition = 1;
-  RubyDiff ifThenBody = 2;
-  RubyDiff ifElseBody = 3;
-}
-
-message Match {
-  RubyDiff matchSubject = 1;
-  RubyDiff matchPatterns = 2;
-}
-
-message Pattern {
-  RubyDiff value = 1;
-  RubyDiff patternBody = 2;
-}
-
-message Retry {
-  RubyDiff value = 1;
-}
-
-message Return {
-  RubyDiff value = 1;
-}
-
-message ScopeEntry {
-  repeated RubyDiff terms = 1;
-}
-
-message ScopeExit {
-  repeated RubyDiff terms = 1;
-}
-
-message Statements {
-  repeated RubyDiff statements = 1;
-}
-
-message Try {
-  RubyDiff tryBody = 1;
-  repeated RubyDiff tryCatch = 2;
-}
-
-message While {
-  RubyDiff whileCondition = 1;
-  RubyDiff whileBody = 2;
-}
-
-message Yield {
-  RubyDiff value = 1;
-}
-
 message RubySyntax {
  oneof syntax {
    Comment comment = 1;
@ -506,6 +121,346 @@ message RubySyntax {
  }
 }

+message Comment {
+  string commentContent = 1;
+}
+
+message Function {
+  repeated RubyDiff functionContext = 1;
+  RubyDiff functionName = 2;
+  repeated RubyDiff functionParameters = 3;
+  RubyDiff functionBody = 4;
+}
+
+message Method {
+  repeated RubyDiff methodContext = 1;
+  RubyDiff methodReceiver = 2;
+  RubyDiff methodName = 3;
+  repeated RubyDiff methodParameters = 4;
+  RubyDiff methodBody = 5;
+}
+
+message File { }
+
+message Line { }
+
+message Plus {
+  RubyDiff lhs = 1;
+  RubyDiff rhs = 2;
+}
+
+message Minus {
+  RubyDiff lhs = 1;
+  RubyDiff rhs = 2;
+}
+
+message Times {
+  RubyDiff lhs = 1;
+  RubyDiff rhs = 2;
+}
+
+message DividedBy {
+  RubyDiff lhs = 1;
+  RubyDiff rhs = 2;
+}
+
+message Modulo {
+  RubyDiff lhs = 1;
+  RubyDiff rhs = 2;
+}
+
+message Power {
+  RubyDiff lhs = 1;
+  RubyDiff rhs = 2;
+}
+
+message Negate {
+  RubyDiff value = 1;
+}
+
+message FloorDivision {
+  RubyDiff lhs = 1;
+  RubyDiff rhs = 2;
+}
+
+message BAnd {
+  RubyDiff left = 1;
+  RubyDiff right = 2;
+}
+
+message BOr {
+  RubyDiff left = 1;
+  RubyDiff right = 2;
+}
+
+message BXOr {
+  RubyDiff left = 1;
+  RubyDiff right = 2;
+}
+
+message LShift {
+  RubyDiff left = 1;
+  RubyDiff right = 2;
+}
+
+message RShift {
+  RubyDiff left = 1;
+  RubyDiff right = 2;
+}
+
+message Complement {
+  RubyDiff value = 1;
+}
+
+message And {
+  RubyDiff lhs = 1;
+  RubyDiff rhs = 2;
+}
+
+message Not {
+  RubyDiff value = 1;
+}
+
+message Or {
+  RubyDiff lhs = 1;
+  RubyDiff rhs = 2;
+}
+
+message XOr {
+  RubyDiff lhs = 1;
+  RubyDiff rhs = 2;
+}
+
+message Call {
+  repeated RubyDiff callContext = 1;
+  RubyDiff callFunction = 2;
+  repeated RubyDiff callParams = 3;
+  RubyDiff callBlock = 4;
+}
+
+message LessThan {
+  RubyDiff lhs = 1;
+  RubyDiff rhs = 2;
+}
+
+message LessThanEqual {
+  RubyDiff lhs = 1;
+  RubyDiff rhs = 2;
+}
+
+message GreaterThan {
+  RubyDiff lhs = 1;
+  RubyDiff rhs = 2;
+}
+
+message GreaterThanEqual {
+  RubyDiff lhs = 1;
+  RubyDiff rhs = 2;
+}
+
+message Equal {
+  RubyDiff lhs = 1;
+  RubyDiff rhs = 2;
+}
+
+message StrictEqual {
+  RubyDiff lhs = 1;
+  RubyDiff rhs = 2;
+}
+
+message Comparison {
+  RubyDiff lhs = 1;
+  RubyDiff rhs = 2;
+}
+
+message Enumeration {
+  RubyDiff enumerationStart = 1;
+  RubyDiff enumerationEnd = 2;
+  RubyDiff enumerationStep = 3;
+}
+
+message Matches {
+  RubyDiff lhs = 1;
+  RubyDiff rhs = 2;
+}
+
+message NotMatches {
+  RubyDiff lhs = 1;
+  RubyDiff rhs = 2;
+}
+
+message MemberAccess {
+  RubyDiff lhs = 1;
+  bytes rhs = 2;
+}
+
+message ScopeResolution {
+  repeated RubyDiff scopes = 1;
+}
+
+message Subscript {
+  RubyDiff lhs = 1;
+  repeated RubyDiff rhs = 2;
+}
+
+message Member {
+  RubyDiff lhs = 1;
+  RubyDiff rhs = 2;
+}
+
+message This { }
+
+message Array {
+  repeated RubyDiff arrayElements = 1;
+}
+
+message Boolean {
+  bool booleanContent = 1;
+}
+
+message Character {
+  string characterContent = 1;
+}
+
+message Complex {
+  string value = 1;
+}
+
+message EscapeSequence {
+  string value = 1;
+}
+
+message Float {
+  string floatContent = 1;
+}
+
+message Hash {
+  repeated RubyDiff hashElements = 1;
+}
+
+message Integer {
+  string integerContent = 1;
+}
+
+message InterpolationElement {
+  RubyDiff interpolationBody = 1;
+}
+
+message KeyValue {
+  RubyDiff key = 1;
+  RubyDiff value = 2;
+}
+
+message Null { }
+
+message Rational {
+  string value = 1;
+}
+
+message Regex {
+  string regexContent = 1;
+}
+
+message String {
+  repeated RubyDiff stringElements = 1;
+}
+
+message Symbol {
+  repeated RubyDiff symbolElements = 1;
+}
+
+message SymbolElement {
+  string symbolContent = 1;
+}
+
+message TextElement {
+  string textElementContent = 1;
+}
+
+message Assignment {
+  repeated RubyDiff assignmentContext = 1;
+  RubyDiff assignmentTarget = 2;
+  RubyDiff assignmentValue = 3;
+}
+
+message Break {
+  RubyDiff value = 1;
+}
+
+message Catch {
+  RubyDiff catchException = 1;
+  RubyDiff catchBody = 2;
+}
+
+message Continue {
+  RubyDiff value = 1;
+}
+
+message Else {
+  RubyDiff elseCondition = 1;
+  RubyDiff elseBody = 2;
+}
+
+message Finally {
+  RubyDiff value = 1;
+}
+
+message ForEach {
+  RubyDiff forEachBinding = 1;
+  RubyDiff forEachSubject = 2;
+  RubyDiff forEachBody = 3;
+}
+
+message If {
+  RubyDiff ifCondition = 1;
+  RubyDiff ifThenBody = 2;
+  RubyDiff ifElseBody = 3;
+}
+
+message Match {
+  RubyDiff matchSubject = 1;
+  RubyDiff matchPatterns = 2;
+}
+
+message Pattern {
+  RubyDiff value = 1;
+  RubyDiff patternBody = 2;
+}
+
+message Retry {
+  RubyDiff value = 1;
+}
+
+message Return {
+  RubyDiff value = 1;
+}
+
+message ScopeEntry {
+  repeated RubyDiff terms = 1;
+}
+
+message ScopeExit {
+  repeated RubyDiff terms = 1;
+}
+
+message Statements {
+  repeated RubyDiff statements = 1;
+}
+
+message Try {
+  RubyDiff tryBody = 1;
+  repeated RubyDiff tryCatch = 2;
+}
+
+message While {
+  RubyDiff whileCondition = 1;
+  RubyDiff whileBody = 2;
+}
+
+message Yield {
+  RubyDiff value = 1;
+}
+
 message Context {
  repeated RubyDiff contextTerms = 1;
  RubyDiff contextSubject = 2;
@ -513,10 +468,55 @@ message Context {

 message Empty { }

+message Error {
+  repeated ErrorSite errorCallStack = 1;
+  repeated string errorExpected = 2;
+  string errorActual = 3;
+  repeated RubyDiff errorChildren = 4;
+}
+
 message Identifier {
  bytes name = 1;
 }

+message Class {
+  RubyDiff classIdentifier = 1;
+  repeated RubyDiff classSuperClass = 2;
+  RubyDiff classBody = 3;
+}
+
+message Load {
+  RubyDiff loadPath = 1;
+  repeated RubyDiff loadWrap = 2;
+}
+
+message LowPrecedenceAnd {
+  RubyDiff lhs = 1;
+  RubyDiff rhs = 2;
+}
+
+message LowPrecedenceOr {
+  RubyDiff lhs = 1;
+  RubyDiff rhs = 2;
+}
+
+message Module {
+  RubyDiff moduleIdentifier = 1;
+  repeated RubyDiff moduleStatements = 2;
+}
+
+message Require {
+  bool requireRelative = 1;
+  RubyDiff requirePath = 2;
+}
+
+message Send {
+  repeated RubyDiff sendReceiver = 1;
+  repeated RubyDiff sendSelector = 2;
+  repeated RubyDiff sendArgs = 3;
+  repeated RubyDiff sendBlock = 4;
+}
+
 message List {
  repeated RubyDiff listContent = 1;
 }
--- a/proto/ruby-terms.proto
+++ b/proto/ruby-terms.proto
@ -12,391 +12,6 @@ message RubyTerm {
  RubySyntax syntax = 1;
 }

-message Comment {
-  string commentContent = 1;
-}
-
-message Function {
-  repeated RubyTerm functionContext = 1;
-  RubyTerm functionName = 2;
-  repeated RubyTerm functionParameters = 3;
-  RubyTerm functionBody = 4;
-}
-
-message Method {
-  repeated RubyTerm methodContext = 1;
-  RubyTerm methodReceiver = 2;
-  RubyTerm methodName = 3;
-  repeated RubyTerm methodParameters = 4;
-  RubyTerm methodBody = 5;
-}
-
-message File { }
-
-message Line { }
-
-message Error {
-  repeated ErrorSite errorCallStack = 1;
-  repeated string errorExpected = 2;
-  string errorActual = 3;
-  repeated RubyTerm errorChildren = 4;
-}
-
-message And {
-  RubyTerm lhs = 1;
-  RubyTerm rhs = 2;
-}
-
-message BAnd {
-  RubyTerm left = 1;
-  RubyTerm right = 2;
-}
-
-message BOr {
-  RubyTerm left = 1;
-  RubyTerm right = 2;
-}
-
-message BXOr {
-  RubyTerm left = 1;
-  RubyTerm right = 2;
-}
-
-message Call {
-  repeated RubyTerm callContext = 1;
-  RubyTerm callFunction = 2;
-  repeated RubyTerm callParams = 3;
-  RubyTerm callBlock = 4;
-}
-
-message Comparison {
-  RubyTerm lhs = 1;
-  RubyTerm rhs = 2;
-}
-
-message Complement {
-  RubyTerm value = 1;
-}
-
-message DividedBy {
-  RubyTerm lhs = 1;
-  RubyTerm rhs = 2;
-}
-
-message Enumeration {
-  RubyTerm enumerationStart = 1;
-  RubyTerm enumerationEnd = 2;
-  RubyTerm enumerationStep = 3;
-}
-
-message Equal {
-  RubyTerm lhs = 1;
-  RubyTerm rhs = 2;
-}
-
-message FloorDivision {
-  RubyTerm lhs = 1;
-  RubyTerm rhs = 2;
-}
-
-message GreaterThan {
-  RubyTerm lhs = 1;
-  RubyTerm rhs = 2;
-}
-
-message GreaterThanEqual {
-  RubyTerm lhs = 1;
-  RubyTerm rhs = 2;
-}
-
-message LShift {
-  RubyTerm left = 1;
-  RubyTerm right = 2;
-}
-
-message LessThan {
-  RubyTerm lhs = 1;
-  RubyTerm rhs = 2;
-}
-
-message LessThanEqual {
-  RubyTerm lhs = 1;
-  RubyTerm rhs = 2;
-}
-
-message Matches {
-  RubyTerm lhs = 1;
-  RubyTerm rhs = 2;
-}
-
-message Member {
-  RubyTerm lhs = 1;
-  RubyTerm rhs = 2;
-}
-
-message MemberAccess {
-  RubyTerm lhs = 1;
-  bytes rhs = 2;
-}
-
-message Minus {
-  RubyTerm lhs = 1;
-  RubyTerm rhs = 2;
-}
-
-message Modulo {
-  RubyTerm lhs = 1;
-  RubyTerm rhs = 2;
-}
-
-message Negate {
-  RubyTerm value = 1;
-}
-
-message Not {
-  RubyTerm value = 1;
-}
-
-message NotMatches {
-  RubyTerm lhs = 1;
-  RubyTerm rhs = 2;
-}
-
-message Or {
-  RubyTerm lhs = 1;
-  RubyTerm rhs = 2;
-}
-
-message Plus {
-  RubyTerm lhs = 1;
-  RubyTerm rhs = 2;
-}
-
-message Power {
-  RubyTerm lhs = 1;
-  RubyTerm rhs = 2;
-}
-
-message RShift {
-  RubyTerm left = 1;
-  RubyTerm right = 2;
-}
-
-message ScopeResolution {
-  repeated RubyTerm scopes = 1;
-}
-
-message StrictEqual {
-  RubyTerm lhs = 1;
-  RubyTerm rhs = 2;
-}
-
-message Subscript {
-  RubyTerm lhs = 1;
-  repeated RubyTerm rhs = 2;
-}
-
-message Times {
-  RubyTerm lhs = 1;
-  RubyTerm rhs = 2;
-}
-
-message XOr {
-  RubyTerm lhs = 1;
-  RubyTerm rhs = 2;
-}
-
-message This { }
-
-message Array {
-  repeated RubyTerm arrayElements = 1;
-}
-
-message Boolean {
-  bool booleanContent = 1;
-}
-
-message Character {
-  string characterContent = 1;
-}
-
-message Complex {
-  string value = 1;
-}
-
-message EscapeSequence {
-  string value = 1;
-}
-
-message Float {
-  string floatContent = 1;
-}
-
-message Hash {
-  repeated RubyTerm hashElements = 1;
-}
-
-message Integer {
-  string integerContent = 1;
-}
-
-message InterpolationElement {
-  RubyTerm interpolationBody = 1;
-}
-
-message KeyValue {
-  RubyTerm key = 1;
-  RubyTerm value = 2;
-}
-
-message Null { }
-
-message Rational {
-  string value = 1;
-}
-
-message Regex {
-  string regexContent = 1;
-}
-
-message String {
-  repeated RubyTerm stringElements = 1;
-}
-
-message Symbol {
-  repeated RubyTerm symbolElements = 1;
-}
-
-message SymbolElement {
-  string symbolContent = 1;
-}
-
-message TextElement {
-  string textElementContent = 1;
-}
-
-message Class {
-  RubyTerm classIdentifier = 1;
-  repeated RubyTerm classSuperClass = 2;
-  RubyTerm classBody = 3;
-}
-
-message Load {
-  RubyTerm loadPath = 1;
-  repeated RubyTerm loadWrap = 2;
-}
-
-message LowPrecedenceAnd {
-  RubyTerm lhs = 1;
-  RubyTerm rhs = 2;
-}
-
-message LowPrecedenceOr {
-  RubyTerm lhs = 1;
-  RubyTerm rhs = 2;
-}
-
-message Module {
-  RubyTerm moduleIdentifier = 1;
-  repeated RubyTerm moduleStatements = 2;
-}
-
-message Require {
-  bool requireRelative = 1;
-  RubyTerm requirePath = 2;
-}
-
-message Send {
-  repeated RubyTerm sendReceiver = 1;
-  repeated RubyTerm sendSelector = 2;
-  repeated RubyTerm sendArgs = 3;
-  repeated RubyTerm sendBlock = 4;
-}
-
-message Assignment {
-  repeated RubyTerm assignmentContext = 1;
-  RubyTerm assignmentTarget = 2;
-  RubyTerm assignmentValue = 3;
-}
-
-message Break {
-  RubyTerm value = 1;
-}
-
-message Catch {
-  RubyTerm catchException = 1;
-  RubyTerm catchBody = 2;
-}
-
-message Continue {
-  RubyTerm value = 1;
-}
-
-message Else {
-  RubyTerm elseCondition = 1;
-  RubyTerm elseBody = 2;
-}
-
-message Finally {
-  RubyTerm value = 1;
-}
-
-message ForEach {
-  RubyTerm forEachBinding = 1;
-  RubyTerm forEachSubject = 2;
-  RubyTerm forEachBody = 3;
-}
-
-message If {
-  RubyTerm ifCondition = 1;
-  RubyTerm ifThenBody = 2;
-  RubyTerm ifElseBody = 3;
-}
-
-message Match {
-  RubyTerm matchSubject = 1;
-  RubyTerm matchPatterns = 2;
-}
-
-message Pattern {
-  RubyTerm value = 1;
-  RubyTerm patternBody = 2;
-}
-
-message Retry {
-  RubyTerm value = 1;
-}
-
-message Return {
-  RubyTerm value = 1;
-}
-
-message ScopeEntry {
-  repeated RubyTerm terms = 1;
-}
-
-message ScopeExit {
-  repeated RubyTerm terms = 1;
-}
-
-message Statements {
-  repeated RubyTerm statements = 1;
-}
-
-message Try {
-  RubyTerm tryBody = 1;
-  repeated RubyTerm tryCatch = 2;
-}
-
-message While {
-  RubyTerm whileCondition = 1;
-  RubyTerm whileBody = 2;
-}
-
-message Yield {
-  RubyTerm value = 1;
-}
-
 message RubySyntax {
  oneof syntax {
    Comment comment = 1;
@ -488,6 +103,346 @@ message RubySyntax {
  }
 }

+message Comment {
+  string commentContent = 1;
+}
+
+message Function {
+  repeated RubyTerm functionContext = 1;
+  RubyTerm functionName = 2;
+  repeated RubyTerm functionParameters = 3;
+  RubyTerm functionBody = 4;
+}
+
+message Method {
+  repeated RubyTerm methodContext = 1;
+  RubyTerm methodReceiver = 2;
+  RubyTerm methodName = 3;
+  repeated RubyTerm methodParameters = 4;
+  RubyTerm methodBody = 5;
+}
+
+message File { }
+
+message Line { }
+
+message Plus {
+  RubyTerm lhs = 1;
+  RubyTerm rhs = 2;
+}
+
+message Minus {
+  RubyTerm lhs = 1;
+  RubyTerm rhs = 2;
+}
+
+message Times {
+  RubyTerm lhs = 1;
+  RubyTerm rhs = 2;
+}
+
+message DividedBy {
+  RubyTerm lhs = 1;
+  RubyTerm rhs = 2;
+}
+
+message Modulo {
+  RubyTerm lhs = 1;
+  RubyTerm rhs = 2;
+}
+
+message Power {
+  RubyTerm lhs = 1;
+  RubyTerm rhs = 2;
+}
+
+message Negate {
+  RubyTerm value = 1;
+}
+
+message FloorDivision {
+  RubyTerm lhs = 1;
+  RubyTerm rhs = 2;
+}
+
+message BAnd {
+  RubyTerm left = 1;
+  RubyTerm right = 2;
+}
+
+message BOr {
+  RubyTerm left = 1;
+  RubyTerm right = 2;
+}
+
+message BXOr {
+  RubyTerm left = 1;
+  RubyTerm right = 2;
+}
+
+message LShift {
+  RubyTerm left = 1;
+  RubyTerm right = 2;
+}
+
+message RShift {
+  RubyTerm left = 1;
+  RubyTerm right = 2;
+}
+
+message Complement {
+  RubyTerm value = 1;
+}
+
+message And {
+  RubyTerm lhs = 1;
+  RubyTerm rhs = 2;
+}
+
+message Not {
+  RubyTerm value = 1;
+}
+
+message Or {
+  RubyTerm lhs = 1;
+  RubyTerm rhs = 2;
+}
+
+message XOr {
+  RubyTerm lhs = 1;
+  RubyTerm rhs = 2;
+}
+
+message Call {
+  repeated RubyTerm callContext = 1;
+  RubyTerm callFunction = 2;
+  repeated RubyTerm callParams = 3;
+  RubyTerm callBlock = 4;
+}
+
+message LessThan {
+  RubyTerm lhs = 1;
+  RubyTerm rhs = 2;
+}
+
+message LessThanEqual {
+  RubyTerm lhs = 1;
+  RubyTerm rhs = 2;
+}
+
+message GreaterThan {
+  RubyTerm lhs = 1;
+  RubyTerm rhs = 2;
+}
+
+message GreaterThanEqual {
+  RubyTerm lhs = 1;
+  RubyTerm rhs = 2;
+}
+
+message Equal {
+  RubyTerm lhs = 1;
+  RubyTerm rhs = 2;
+}
+
+message StrictEqual {
+  RubyTerm lhs = 1;
+  RubyTerm rhs = 2;
+}
+
+message Comparison {
+  RubyTerm lhs = 1;
+  RubyTerm rhs = 2;
+}
+
+message Enumeration {
+  RubyTerm enumerationStart = 1;
+  RubyTerm enumerationEnd = 2;
+  RubyTerm enumerationStep = 3;
+}
+
+message Matches {
+  RubyTerm lhs = 1;
+  RubyTerm rhs = 2;
+}
+
+message NotMatches {
+  RubyTerm lhs = 1;
+  RubyTerm rhs = 2;
+}
+
+message MemberAccess {
+  RubyTerm lhs = 1;
+  bytes rhs = 2;
+}
+
+message ScopeResolution {
+  repeated RubyTerm scopes = 1;
+}
+
+message Subscript {
+  RubyTerm lhs = 1;
+  repeated RubyTerm rhs = 2;
+}
+
+message Member {
+  RubyTerm lhs = 1;
+  RubyTerm rhs = 2;
+}
+
+message This { }
+
+message Array {
+  repeated RubyTerm arrayElements = 1;
+}
+
+message Boolean {
+  bool booleanContent = 1;
+}
+
+message Character {
+  string characterContent = 1;
+}
+
+message Complex {
+  string value = 1;
+}
+
+message EscapeSequence {
+  string value = 1;
+}
+
+message Float {
+  string floatContent = 1;
+}
+
+message Hash {
+  repeated RubyTerm hashElements = 1;
+}
+
+message Integer {
+  string integerContent = 1;
+}
+
+message InterpolationElement {
+  RubyTerm interpolationBody = 1;
+}
+
+message KeyValue {
+  RubyTerm key = 1;
+  RubyTerm value = 2;
+}
+
+message Null { }
+
+message Rational {
+  string value = 1;
+}
+
+message Regex {
+  string regexContent = 1;
+}
+
+message String {
+  repeated RubyTerm stringElements = 1;
+}
+
+message Symbol {
+  repeated RubyTerm symbolElements = 1;
+}
+
+message SymbolElement {
+  string symbolContent = 1;
+}
+
+message TextElement {
+  string textElementContent = 1;
+}
+
+message Assignment {
+  repeated RubyTerm assignmentContext = 1;
+  RubyTerm assignmentTarget = 2;
+  RubyTerm assignmentValue = 3;
+}
+
+message Break {
+  RubyTerm value = 1;
+}
+
+message Catch {
+  RubyTerm catchException = 1;
+  RubyTerm catchBody = 2;
+}
+
+message Continue {
+  RubyTerm value = 1;
+}
+
+message Else {
+  RubyTerm elseCondition = 1;
+  RubyTerm elseBody = 2;
+}
+
+message Finally {
+  RubyTerm value = 1;
+}
+
+message ForEach {
+  RubyTerm forEachBinding = 1;
+  RubyTerm forEachSubject = 2;
+  RubyTerm forEachBody = 3;
+}
+
+message If {
+  RubyTerm ifCondition = 1;
+  RubyTerm ifThenBody = 2;
+  RubyTerm ifElseBody = 3;
+}
+
+message Match {
+  RubyTerm matchSubject = 1;
+  RubyTerm matchPatterns = 2;
+}
+
+message Pattern {
+  RubyTerm value = 1;
+  RubyTerm patternBody = 2;
+}
+
+message Retry {
+  RubyTerm value = 1;
+}
+
+message Return {
+  RubyTerm value = 1;
+}
+
+message ScopeEntry {
+  repeated RubyTerm terms = 1;
+}
+
+message ScopeExit {
+  repeated RubyTerm terms = 1;
+}
+
+message Statements {
+  repeated RubyTerm statements = 1;
+}
+
+message Try {
+  RubyTerm tryBody = 1;
+  repeated RubyTerm tryCatch = 2;
+}
+
+message While {
+  RubyTerm whileCondition = 1;
+  RubyTerm whileBody = 2;
+}
+
+message Yield {
+  RubyTerm value = 1;
+}
+
 message Context {
  repeated RubyTerm contextTerms = 1;
  RubyTerm contextSubject = 2;
@ -495,10 +450,55 @@ message Context {

 message Empty { }

+message Error {
+  repeated ErrorSite errorCallStack = 1;
+  repeated string errorExpected = 2;
+  string errorActual = 3;
+  repeated RubyTerm errorChildren = 4;
+}
+
 message Identifier {
  bytes name = 1;
 }

+message Class {
+  RubyTerm classIdentifier = 1;
+  repeated RubyTerm classSuperClass = 2;
+  RubyTerm classBody = 3;
+}
+
+message Load {
+  RubyTerm loadPath = 1;
+  repeated RubyTerm loadWrap = 2;
+}
+
+message LowPrecedenceAnd {
+  RubyTerm lhs = 1;
+  RubyTerm rhs = 2;
+}
+
+message LowPrecedenceOr {
+  RubyTerm lhs = 1;
+  RubyTerm rhs = 2;
+}
+
+message Module {
+  RubyTerm moduleIdentifier = 1;
+  repeated RubyTerm moduleStatements = 2;
+}
+
+message Require {
+  bool requireRelative = 1;
+  RubyTerm requirePath = 2;
+}
+
+message Send {
+  repeated RubyTerm sendReceiver = 1;
+  repeated RubyTerm sendSelector = 2;
+  repeated RubyTerm sendArgs = 3;
+  repeated RubyTerm sendBlock = 4;
+}
+
 message List {
  repeated RubyTerm listContent = 1;
 }
--- a/proto/typescript-diffs.proto
+++ b/proto/typescript-diffs.proto
@ -30,22 +30,6 @@ message TypeScriptDiff {
  }
 }

-message Alias {
-  bytes aliasValue = 1;
-  bytes aliasName = 2;
-}
-
-message ImportPath {
-  string unPath = 1;
-  IsRelative pathIsRelative = 2;
-}
-
-enum IsRelative {
-  Unknown = 0;
-  Relative = 1;
-  NonRelative = 2;
-}
-
 message TypeScriptSyntax {
  oneof syntax {
    Comment comment = 1;
@ -819,10 +803,6 @@ message AbstractClass {
  TypeScriptDiff classBody = 4;
 }

-message ExtendsClause {
-  repeated TypeScriptDiff extendsClauses = 1;
-}
-
 message ImplementsClause {
  repeated TypeScriptDiff implementsClauseTypes = 1;
 }
@ -898,6 +878,10 @@ message EnumDeclaration {
  repeated TypeScriptDiff enumDeclarationBody = 2;
 }

+message ExtendsClause {
+  repeated TypeScriptDiff extendsClauses = 1;
+}
+
 message AmbientFunction {
  repeated TypeScriptDiff ambientFunctionContext = 1;
  TypeScriptDiff ambientFunctionIdentifier = 2;
@ -980,3 +964,19 @@ message JavaScriptRequire {
 message List {
  repeated TypeScriptDiff listContent = 1;
 }
+
+message Alias {
+  bytes aliasValue = 1;
+  bytes aliasName = 2;
+}
+
+message ImportPath {
+  string unPath = 1;
+  IsRelative pathIsRelative = 2;
+}
+
+enum IsRelative {
+  Unknown = 0;
+  Relative = 1;
+  NonRelative = 2;
+}
--- a/proto/typescript-terms.proto
+++ b/proto/typescript-terms.proto
@ -12,22 +12,6 @@ message TypeScriptTerm {
  TypeScriptSyntax syntax = 1;
 }

-message Alias {
-  bytes aliasValue = 1;
-  bytes aliasName = 2;
-}
-
-message ImportPath {
-  string unPath = 1;
-  IsRelative pathIsRelative = 2;
-}
-
-enum IsRelative {
-  Unknown = 0;
-  Relative = 1;
-  NonRelative = 2;
-}
-
 message TypeScriptSyntax {
  oneof syntax {
    Comment comment = 1;
@ -801,10 +785,6 @@ message AbstractClass {
  TypeScriptTerm classBody = 4;
 }

-message ExtendsClause {
-  repeated TypeScriptTerm extendsClauses = 1;
-}
-
 message ImplementsClause {
  repeated TypeScriptTerm implementsClauseTypes = 1;
 }
@ -880,6 +860,10 @@ message EnumDeclaration {
  repeated TypeScriptTerm enumDeclarationBody = 2;
 }

+message ExtendsClause {
+  repeated TypeScriptTerm extendsClauses = 1;
+}
+
 message AmbientFunction {
  repeated TypeScriptTerm ambientFunctionContext = 1;
  TypeScriptTerm ambientFunctionIdentifier = 2;
@ -962,3 +946,19 @@ message JavaScriptRequire {
 message List {
  repeated TypeScriptTerm listContent = 1;
 }
+
+message Alias {
+  bytes aliasValue = 1;
+  bytes aliasName = 2;
+}
+
+message ImportPath {
+  string unPath = 1;
+  IsRelative pathIsRelative = 2;
+}
+
+enum IsRelative {
+  Unknown = 0;
+  Relative = 1;
+  NonRelative = 2;
+}
--- a/semantic.cabal
+++ b/semantic.cabal
@ -173,6 +173,7 @@ library
                     , Semantic.Graph
                     , Semantic.IO
                     , Semantic.Parse
+                     , Semantic.REPL
                     , Semantic.Resolution
                     , Semantic.Task
                     , Semantic.Telemetry
@ -211,6 +212,7 @@ library
                     , gitrev
                     , Glob
                     , hashable
+                     , haskeline
                     , hscolour
                     , http-client
                     , http-client-tls
@ -324,12 +326,10 @@ test-suite test
                     , Test.Hspec.LeanCheck
  build-depends:       aeson
                     , algebraic-graphs
-                     , array
                     , async
                     , base
                     , bifunctors
                     , bytestring
-                     , comonad
                     , containers
                     , effects
                     , fastsum
@ -382,7 +382,6 @@ test-suite doctests
  ghc-options:         -dynamic -threaded -j
  build-depends:       base
                     , doctest
-                     , QuickCheck

 benchmark evaluation
  hs-source-dirs:      bench
--- a/src/Control/Abstract/Evaluator.hs
+++ b/src/Control/Abstract/Evaluator.hs
@ -23,6 +23,7 @@ import Control.Monad.Effect.Reader    as X
 import Control.Monad.Effect.Resumable as X
 import Control.Monad.Effect.State     as X
 import Control.Monad.Effect.Trace     as X
+import Control.Monad.IO.Class
 import Prologue hiding (MonadError(..))

 -- | An 'Evaluator' is a thin wrapper around 'Eff' with (phantom) type parameters for the address, term, and value types.
@ -34,6 +35,7 @@ newtype Evaluator address value effects a = Evaluator { runEvaluator :: Eff effe
  deriving (Applicative, Effectful, Functor, Monad)

 deriving instance Member NonDet effects => Alternative (Evaluator address value effects)
+deriving instance Member (Lift IO) effects => MonadIO (Evaluator address value effects)

 -- Effects

--- a/src/Control/Abstract/TermEvaluator.hs
+++ b/src/Control/Abstract/TermEvaluator.hs
@ -13,6 +13,7 @@ import Control.Monad.Effect.Reader    as X
 import Control.Monad.Effect.Resumable as X
 import Control.Monad.Effect.State     as X
 import Control.Monad.Effect.Trace     as X
+import Control.Monad.IO.Class
 import Prologue

 -- | Evaluators specialized to some specific term type.
@ -22,6 +23,7 @@ newtype TermEvaluator term address value effects a = TermEvaluator { runTermEval
  deriving (Applicative, Effectful, Functor, Monad)

 deriving instance Member NonDet effects => Alternative (TermEvaluator term address value effects)
+deriving instance Member (Lift IO) effects => MonadIO (TermEvaluator term address value effects)


 raiseHandler :: (Evaluator address value effects a -> Evaluator address value effects' a') -> (TermEvaluator term address value effects a -> TermEvaluator term address value effects' a')
--- a/src/Data/Abstract/Environment.hs
+++ b/src/Data/Abstract/Environment.hs
@ -37,7 +37,7 @@ import           Prologue

 -- | A map of names to values. Represents a single scope level of an environment chain.
 newtype Bindings address = Bindings { unBindings :: Map.Map Name address }
-  deriving (Eq, Ord, Show)
+  deriving (Eq, Ord)

 instance Semigroup (Bindings address) where
  (<>) (Bindings a) (Bindings b) = Bindings (a <> b)
@ -49,6 +49,10 @@ instance Monoid (Bindings address) where
 instance Lower (Bindings address) where
  lowerBound = mempty

+instance Show address => Show (Bindings address) where
+  showsPrec d = showsUnaryWith showsPrec "Bindings" d . pairs
+
+
 -- | A LIFO stack of maps of names to addresses, representing a lexically-scoped evaluation environment.
 --   All behaviors can be assumed to be frontmost-biased: looking up "a" will check the most specific
 --   scope for "a", then the next, and so on.
--- a/src/Data/Abstract/Evaluatable.hs
+++ b/src/Data/Abstract/Evaluatable.hs
@ -2,6 +2,8 @@
 module Data.Abstract.Evaluatable
 ( module X
 , Evaluatable(..)
+, ModuleEffects
+, ValueEffects
 , evaluate
 , traceResolve
 -- * Preludes
@ -75,6 +77,19 @@ class (Show1 constr, Foldable constr) => Evaluatable constr where
    rvalBox v


+type ModuleEffects address value rest
+  =  Exc (LoopControl address)
+  ': Exc (Return address)
+  ': Env address
+  ': Deref value
+  ': Allocator address
+  ': Reader ModuleInfo
+  ': rest
+
+type ValueEffects address value rest
+  =  Function address value
+  ': rest
+
 evaluate :: ( AbstractValue address value valueEffects
            , Declarations term
            , Effects effects
@ -96,8 +111,8 @@ evaluate :: ( AbstractValue address value valueEffects
            , Member Trace effects
            , Ord address
            , Recursive term
-            , moduleEffects ~ (Exc (LoopControl address) ': Exc (Return address) ': Env address ': Deref value ': Allocator address ': Reader ModuleInfo ': effects)
-            , valueEffects ~ (Function address value ': moduleEffects)
+            , moduleEffects ~ ModuleEffects address value effects
+            , valueEffects ~ ValueEffects address value moduleEffects
            )
         => proxy lang
         -> (SubtermAlgebra Module      term (TermEvaluator term address value moduleEffects address)           -> SubtermAlgebra Module      term (TermEvaluator term address value moduleEffects address))
--- a/src/Data/Abstract/Heap.hs
+++ b/src/Data/Abstract/Heap.hs
@ -52,4 +52,4 @@ instance (Ord address, Ord value) => Reducer (address, value) (Heap address valu
  snoc (Heap heap) (addr, a) = Heap (snoc heap (addr, a))

 instance (Show address, Show value) => Show (Heap address value) where
-  showsPrec d = showsUnaryWith showsPrec "Heap" d . Monoidal.pairs . unHeap
+  showsPrec d = showsUnaryWith showsPrec "Heap" d . map (second toList) . Monoidal.pairs . unHeap
--- a/src/Data/Error.hs
+++ b/src/Data/Error.hs
@ -4,15 +4,15 @@ module Data.Error
  , formatError
  , makeError
  , showExpectation
+  , showExcerpt
  , withSGRCode
  ) where

 import Prologue

-import Data.ByteString (isSuffixOf)
-import Data.ByteString.Char8 (pack, unpack)
+import Data.ByteString.Char8 (unpack)
 import Data.Ix (inRange)
-import Data.List (intersperse)
+import Data.List (intersperse, isSuffixOf)
 import System.Console.ANSI

 import Data.Blob
@ -43,19 +43,29 @@ type Colourize = Bool

 -- | Format an 'Error', optionally with reference to the source where it occurred.
 formatError :: IncludeSource -> Colourize -> Blob -> Error String -> String
-formatError includeSource colourize Blob{..} Error{..}
+formatError includeSource colourize blob@Blob{..} Error{..}
  = ($ "")
  $ withSGRCode colourize [SetConsoleIntensity BoldIntensity] (showSpan path errorSpan . showString ": ")
  . withSGRCode colourize [SetColor Foreground Vivid Red] (showString "error") . showString ": " . showExpectation colourize errorExpected errorActual . showChar '\n'
-  . (if includeSource
-    then showString (unpack context) . (if "\n" `isSuffixOf` context then id else showChar '\n')
-       . showString (replicate (succ (posColumn (spanStart errorSpan) + lineNumberDigits)) ' ') . withSGRCode colourize [SetColor Foreground Vivid Green] (showChar '^' . showChar '\n')
-    else id)
+  . (if includeSource then showExcerpt colourize errorSpan blob else id)
  . showCallStack colourize callStack . showChar '\n'
-  where context = maybe "\n" (sourceBytes . sconcat) (nonEmpty [ fromUTF8 (pack (showLineNumber i)) <> fromUTF8 ": " <> l | (i, l) <- zip [1..] (sourceLines blobSource), inRange (posLine (spanStart errorSpan) - 2, posLine (spanStart errorSpan)) i ])
+  where
+    path = Just $ if includeSource then blobPath else "<filtered>"
+
+showExcerpt :: Colourize -> Span -> Blob -> ShowS
+showExcerpt colourize Span{..} Blob{..}
+  = showString context . (if "\n" `isSuffixOf` context then id else showChar '\n')
+  . showString (replicate (caretPaddingWidth + lineNumberDigits) ' ') . withSGRCode colourize [SetColor Foreground Vivid Green] (showString caret) . showChar '\n'
+  where context = fold contextLines
+        contextLines = [ showLineNumber i <> ": " <> unpack (sourceBytes l)
+                       | (i, l) <- zip [1..] (sourceLines blobSource)
+                       , inRange (posLine spanStart - 2, posLine spanStart) i
+                       ]
        showLineNumber n = let s = show n in replicate (lineNumberDigits - length s) ' ' <> s
-        lineNumberDigits = succ (floor (logBase 10 (fromIntegral (posLine (spanStart errorSpan)) :: Double)))
-        path = Just $ if includeSource then blobPath else "<filtered>"
+        lineNumberDigits = succ (floor (logBase 10 (fromIntegral (posLine spanStart) :: Double)))
+        caretPaddingWidth = succ (posColumn spanStart)
+        caret | posLine spanStart == posLine spanEnd = replicate (max 1 (posColumn spanEnd - posColumn spanStart)) '^'
+              | otherwise                            = "^..."

 withSGRCode :: Colourize -> [SGR] -> ShowS -> ShowS
 withSGRCode useColour code content =
--- a/src/Semantic/Config.hs
+++ b/src/Semantic/Config.hs
@ -8,6 +8,7 @@ module Semantic.Config
  , debugOptions
  , lookupStatsAddr
  , withHaystackFromConfig
+  , logOptionsFromConfig
  , withLoggerFromConfig
  , withStatterFromConfig
  , withTelemetry
@ -93,19 +94,23 @@ withTelemetry config action =
  withStatterFromConfig config $ \statter ->
    action (TelemetryQueues logger statter haystack)

+logOptionsFromConfig :: Config -> LogOptions
+logOptionsFromConfig Config{..} = LogOptions
+  { logOptionsLevel     = optionsLogLevel configOptions
+  , logOptionsFormatter = configLogFormatter
+  , logOptionsContext   = logOptionsContext' configIsTerminal
+  }
+  where logOptionsContext' = \case
+          False -> [ ("app", configAppName)
+                   , ("pid", show configProcessID)
+                   , ("hostname", configHostName)
+                   , ("sha", buildSHA)
+                   ] <> [("request_id", x) | x <- toList (optionsRequestID configOptions) ]
+          _ -> []
+
+
 withLoggerFromConfig :: Config -> (LogQueue -> IO c) -> IO c
-withLoggerFromConfig Config{..} = withLogger opts configMaxTelemetyQueueSize
-  where opts = LogOptions { logOptionsLevel     = optionsLogLevel configOptions
-                          , logOptionsFormatter = configLogFormatter
-                          , logOptionsContext   = logOptionsContext' configIsTerminal
-                          }
-        logOptionsContext' = \case
-                            False -> [ ("app", configAppName)
-                                     , ("pid", show configProcessID)
-                                     , ("hostname", configHostName)
-                                     , ("sha", buildSHA)
-                                     ] <> [("request_id", x) | x <- toList (optionsRequestID configOptions) ]
-                            _ -> []
+withLoggerFromConfig config = withLogger (logOptionsFromConfig config) (configMaxTelemetyQueueSize config)


 withHaystackFromConfig :: Config -> Haystack.ErrorLogger -> (HaystackQueue -> IO c) -> IO c
--- a/src/Semantic/Graph.hs
+++ b/src/Semantic/Graph.hs
@ -8,7 +8,7 @@ module Semantic.Graph
 , GraphType(..)
 , Graph
 , Vertex
-, ImportGraphEff(..)
+, ConcreteEff(..)
 , style
 , parsePackage
 , withTermSpans
@ -41,6 +41,7 @@ import           Data.Abstract.Package as Package
 import           Data.Abstract.Value.Abstract as Abstract
 import           Data.Abstract.Value.Concrete as Concrete (Value, ValueError (..), runFunction, runValueErrorWith)
 import           Data.Abstract.Value.Type as Type
+import           Data.Blob
 import           Data.Coerce
 import           Data.Graph
 import           Data.Graph.Vertex (VertexDeclarationStrategy, VertexDeclarationWithStrategy)
@ -66,11 +67,11 @@ runGraph :: forall effs. (Member Distribute effs, Member (Exc SomeException) eff
         -> Eff effs (Graph Vertex)
 runGraph ImportGraph _ project
  | SomeAnalysisParser parser lang <- someAnalysisParser (Proxy :: Proxy AnalysisClasses) (projectLanguage project) = do
-    package <- parsePackage parser project
+    package <- fmap snd <$> parsePackage parser project
    runImportGraphToModuleInfos lang package
 runGraph CallGraph includePackages project
  | SomeAnalysisParser parser lang <- someAnalysisParser (Proxy :: Proxy AnalysisClasses) (projectLanguage project) = do
-    package <- parsePackage parser project
+    package <- fmap snd <$> parsePackage parser project
    modules <- topologicalSort <$> runImportGraphToModules lang package
    runCallGraph lang includePackages modules package

@ -122,40 +123,37 @@ runCallGraph lang includePackages modules package = do
        . Hole.runDeref (Located.handleDeref Monovariant.handleDeref)
  extractGraph <$> runEvaluator (runGraphAnalysis (evaluate lang analyzeModule analyzeTerm runAddressEffects Abstract.runFunction modules))

-runImportGraphToModuleInfos :: forall effs lang term.
-                  ( Declarations term
-                  , Evaluatable (Base term)
-                  , FreeVariables term
-                  , HasPrelude lang
-                  , HasPostlude lang
-                  , Member Trace effs
-                  , Recursive term
-                  , Effects effs
-                  )
-               => Proxy lang
-               -> Package term
-               -> Eff effs (Graph Vertex)
+runImportGraphToModuleInfos :: ( Declarations term
+                               , Evaluatable (Base term)
+                               , FreeVariables term
+                               , HasPrelude lang
+                               , HasPostlude lang
+                               , Member Trace effs
+                               , Recursive term
+                               , Effects effs
+                               )
+                            => Proxy lang
+                            -> Package term
+                            -> Eff effs (Graph Vertex)
 runImportGraphToModuleInfos lang (package :: Package term) = runImportGraph lang package allModuleInfos
  where allModuleInfos info = maybe (vertex (unknownModuleVertex info)) (foldMap (vertex . moduleVertex . moduleInfo)) (ModuleTable.lookup (modulePath info) (packageModules package))

-runImportGraphToModules :: forall effs lang term.
-                  ( Declarations term
-                  , Evaluatable (Base term)
-                  , FreeVariables term
-                  , HasPrelude lang
-                  , HasPostlude lang
-                  , Member Trace effs
-                  , Recursive term
-                  , Effects effs
-                  )
-               => Proxy lang
-               -> Package term
-               -> Eff effs (Graph (Module term))
+runImportGraphToModules :: ( Declarations term
+                           , Evaluatable (Base term)
+                           , FreeVariables term
+                           , HasPrelude lang
+                           , HasPostlude lang
+                           , Member Trace effs
+                           , Recursive term
+                           , Effects effs
+                           )
+                        => Proxy lang
+                        -> Package term
+                        -> Eff effs (Graph (Module term))
 runImportGraphToModules lang (package :: Package term) = runImportGraph lang package resolveOrLowerBound
  where resolveOrLowerBound info = maybe lowerBound (foldMap vertex) (ModuleTable.lookup (modulePath info) (packageModules package))

-runImportGraph :: forall effs lang term vertex.
-                  ( Declarations term
+runImportGraph :: ( Declarations term
                  , Evaluatable (Base term)
                  , FreeVariables term
                  , HasPrelude lang
@ -170,9 +168,10 @@ runImportGraph :: forall effs lang term vertex.
               -> Eff effs (Graph vertex)
 runImportGraph lang (package :: Package term) f =
  let analyzeModule = graphingModuleInfo
-      extractGraph (_, (graph, _)) = graph >>= f
+      extractGraph (graph, _) = graph >>= f
      runImportGraphAnalysis
        = runState lowerBound
+        . runState lowerBound
        . runFresh 0
        . resumingLoadError
        . resumingUnspecialized
@ -181,10 +180,9 @@ runImportGraph lang (package :: Package term) f =
        . resumingResolutionError
        . resumingAddressError
        . resumingValueError
-        . runState lowerBound
        . runReader lowerBound
        . runModules (ModuleTable.modulePaths (packageModules package))
-        . runTermEvaluator @_ @_ @(Value (Hole (Maybe Name) Precise) (ImportGraphEff (Hole (Maybe Name) Precise) effs))
+        . runTermEvaluator @_ @_ @(Value (Hole (Maybe Name) Precise) (ConcreteEff (Hole (Maybe Name) Precise) _))
        . runReader (packageInfo package)
        . runReader lowerBound
      runAddressEffects
@ -192,30 +190,26 @@ runImportGraph lang (package :: Package term) f =
        . Hole.runDeref Precise.handleDeref
  in extractGraph <$> runEvaluator (runImportGraphAnalysis (evaluate lang analyzeModule id runAddressEffects (Concrete.runFunction coerce coerce) (ModuleTable.toPairs (packageModules package) >>= toList . snd)))

-newtype ImportGraphEff address outerEffects a = ImportGraphEff
-  { runImportGraphEff :: Eff (  Function address (Value address (ImportGraphEff address outerEffects))
-                             ': Exc (LoopControl address)
-                             ': Exc (Return address)
-                             ': Env address
-                             ': Deref (Value address (ImportGraphEff address outerEffects))
-                             ': Allocator address
-                             ': Reader ModuleInfo
-                             ': Reader Span
-                             ': Reader PackageInfo
-                             ': Modules address
-                             ': Reader (ModuleTable (NonEmpty (Module (ModuleResult address))))
-                             ': State (Graph ModuleInfo)
-                             ': Resumable (BaseError (ValueError address (ImportGraphEff address outerEffects)))
-                             ': Resumable (BaseError (AddressError address (Value address (ImportGraphEff address outerEffects))))
-                             ': Resumable (BaseError ResolutionError)
-                             ': Resumable (BaseError EvalError)
-                             ': Resumable (BaseError (EnvironmentError address))
-                             ': Resumable (BaseError (UnspecializedError (Value address (ImportGraphEff address outerEffects))))
-                             ': Resumable (BaseError (LoadError address))
-                             ': Fresh
-                             ': State (Heap address (Value address (ImportGraphEff address outerEffects)))
-                             ': outerEffects
-                             ) a
+type ConcreteEffects address rest
+  =  Reader Span
+  ': Reader PackageInfo
+  ': Modules address
+  ': Reader (ModuleTable (NonEmpty (Module (ModuleResult address))))
+  ': Resumable (BaseError (ValueError address (ConcreteEff address rest)))
+  ': Resumable (BaseError (AddressError address (Value address (ConcreteEff address rest))))
+  ': Resumable (BaseError ResolutionError)
+  ': Resumable (BaseError EvalError)
+  ': Resumable (BaseError (EnvironmentError address))
+  ': Resumable (BaseError (UnspecializedError (Value address (ConcreteEff address rest))))
+  ': Resumable (BaseError (LoadError address))
+  ': Fresh
+  ': State (Heap address (Value address (ConcreteEff address rest)))
+  ': rest
+
+newtype ConcreteEff address outerEffects a = ConcreteEff
+  { runConcreteEff :: Eff (ValueEffects  address (Value address (ConcreteEff address outerEffects))
+                          (ModuleEffects address (Value address (ConcreteEff address outerEffects))
+                          (ConcreteEffects address outerEffects))) a
  }


@ -223,8 +217,8 @@ newtype ImportGraphEff address outerEffects a = ImportGraphEff
 parsePackage :: (Member Distribute effs, Member (Exc SomeException) effs, Member Resolution effs, Member Task effs, Member Trace effs)
             => Parser term -- ^ A parser.
             -> Project     -- ^ Project to parse into a package.
-             -> Eff effs (Package term)
-parsePackage parser project@Project{..} = do
+             -> Eff effs (Package (Blob, term))
+parsePackage parser project = do
  p <- parseModules parser project
  resMap <- Task.resolutionMap project
  let pkg = Package.fromModules n p resMap
@ -233,17 +227,13 @@ parsePackage parser project@Project{..} = do
  where
    n = name (projectName project)

-    -- | Parse all files in a project into 'Module's.
-    parseModules :: (Member Distribute effs, Member (Exc SomeException) effs, Member Task effs) => Parser term -> Project -> Eff effs [Module term]
-    parseModules parser p@Project{..} = distributeFor (projectFiles p) (parseModule p parser)
+    parseModules parser p = distributeFor (projectFiles p) (parseModule p parser)

-- | Parse a file into a 'Module'.
-parseModule :: (Member (Exc SomeException) effs, Member Task effs) => Project -> Parser term -> File -> Eff effs (Module term)
-parseModule proj parser file = do
-  mBlob <- readFile proj file
-  case mBlob of
-    Just blob -> moduleForBlob (Just (projectRootDir proj)) blob <$> parse parser blob
-    Nothing   -> throwError (SomeException (FileNotFound (filePath file)))
+    parseModule proj parser file = do
+      mBlob <- readFile proj file
+      case mBlob of
+        Just blob -> moduleForBlob (Just (projectRootDir proj)) blob . (,) blob <$> parse parser blob
+        Nothing   -> throwError (SomeException (FileNotFound (filePath file)))

 withTermSpans :: ( HasField fields Span
                 , Member (Reader Span) effects
--- a/src/Semantic/REPL.hs
+++ b/src/Semantic/REPL.hs
@ -0,0 +1,210 @@
+{-# LANGUAGE GADTs, KindSignatures, LambdaCase, TypeOperators #-}
+{-# OPTIONS_GHC -Wno-missing-signatures #-}
+module Semantic.REPL
+( rubyREPL
+) where
+
+import Control.Abstract hiding (Continue, List, string)
+import Control.Monad.IO.Class
+import Data.Abstract.Address.Precise as Precise
+import Data.Abstract.Environment as Env
+import Data.Abstract.Evaluatable hiding (string)
+import Data.Abstract.Module
+import Data.Abstract.ModuleTable as ModuleTable
+import Data.Abstract.Package
+import Data.Abstract.Value.Concrete as Concrete
+import Data.Blob (Blob(..))
+import Data.Coerce
+import Data.Error (showExcerpt)
+import Data.Graph (topologicalSort)
+import Data.Language as Language
+import Data.List (uncons)
+import Data.Project
+import Data.Quieterm
+import Data.Span
+import qualified Data.Time.Clock.POSIX as Time (getCurrentTime)
+import qualified Data.Time.LocalTime as LocalTime
+import Numeric (readDec)
+import Parsing.Parser (rubyParser)
+import Prologue hiding (throwError)
+import Semantic.Config (logOptionsFromConfig)
+import Semantic.Distribute
+import Semantic.Graph
+import Semantic.IO as IO
+import Semantic.Resolution
+import Semantic.Task hiding (Error)
+import Semantic.Telemetry
+import Semantic.Telemetry.Log (LogOptions, Message(..), writeLogMessage)
+import Semantic.Util
+import System.Console.Haskeline
+import System.Directory (createDirectoryIfMissing, getHomeDirectory)
+import System.FilePath
+
+data REPL (m :: * -> *) result where
+  Prompt :: REPL m (Maybe String)
+  Output :: String -> REPL m ()
+
+prompt :: (Effectful m, Member REPL effects) => m effects (Maybe String)
+prompt = send Prompt
+
+output :: (Effectful m, Member REPL effects) => String -> m effects ()
+output s = send (Output s)
+
+
+data Quit = Quit
+  deriving Show
+
+instance Exception Quit
+
+
+instance PureEffect REPL
+instance Effect REPL where
+  handleState state handler (Request Prompt k) = Request Prompt (handler . (<$ state) . k)
+  handleState state handler (Request (Output s) k) = Request (Output s) (handler . (<$ state) . k)
+
+
+runREPL :: (Effectful m, MonadIO (m effects), PureEffects effects) => Prefs -> Settings IO -> m (REPL ': effects) a -> m effects a
+runREPL prefs settings = interpret $ \case
+  Prompt   -> liftIO (runInputTWithPrefs prefs settings (getInputLine (cyan <> "repl: " <> plain)))
+  Output s -> liftIO (runInputTWithPrefs prefs settings (outputStrLn s))
+
+rubyREPL = repl (Proxy @'Language.Ruby) rubyParser
+
+repl proxy parser paths = defaultConfig debugOptions >>= \ config -> runM . runDistribute . runError @_ @_ @SomeException . runTelemetryIgnoringStat (logOptionsFromConfig config) . runTraceInTelemetry . runReader config . IO.runFiles . runResolution . runTaskF $ do
+  blobs <- catMaybes <$> traverse IO.readFile (flip File (Language.reflect proxy) <$> paths)
+  package <- fmap (fmap quieterm) <$> parsePackage parser (Project (takeDirectory (maybe "/" fst (uncons paths))) blobs (Language.reflect proxy) [])
+  modules <- topologicalSort <$> runImportGraphToModules proxy (snd <$> package)
+  homeDir <- liftIO getHomeDirectory
+  prefs <- liftIO (readPrefs (homeDir <> "/.haskeline"))
+  let settingsDir = homeDir <> "/.local/semantic"
+  liftIO $ createDirectoryIfMissing True settingsDir
+  let settings = Settings
+        { complete = noCompletion
+        , historyFile = Just (settingsDir <> "/repl_history")
+        , autoAddHistory = True
+        }
+  runEvaluator
+    . runREPL prefs settings
+    . fmap snd
+    . runState ([] @Breakpoint)
+    . runReader Step
+    . runTermEvaluator @_ @_ @(Value Precise (ConcreteEff Precise _))
+    . runPrintingTrace
+    . runState lowerBound
+    . runFresh 0
+    . fmap reassociate
+    . runLoadError
+    . runUnspecialized
+    . runEnvironmentError
+    . runEvalError
+    . runResolutionError
+    . runAddressError
+    . runValueError
+    . runReader (lowerBound @(ModuleTable (NonEmpty (Module (ModuleResult Precise)))))
+    . raiseHandler (runModules (ModuleTable.modulePaths (packageModules (snd <$> package))))
+    . runReader (packageInfo package)
+    . runReader (lowerBound @Span)
+    $ evaluate proxy id (withTermSpans . step (fmap (\ (x:|_) -> moduleBody x) <$> ModuleTable.toPairs (packageModules (fst <$> package)))) (Precise.runAllocator . Precise.runDeref) (Concrete.runFunction coerce coerce) modules
+
+-- TODO: REPL for typechecking/abstract semantics
+-- TODO: drive the flow from within the REPL instead of from without
+
+runTelemetryIgnoringStat :: (Effectful m, MonadIO (m effects), PureEffects effects) => LogOptions -> m (Telemetry : effects) a -> m effects a
+runTelemetryIgnoringStat logOptions = interpret $ \case
+  WriteStat{} -> pure ()
+  WriteLog level message pairs -> do
+    time <- liftIO Time.getCurrentTime
+    zonedTime <- liftIO (LocalTime.utcToLocalZonedTime time)
+    writeLogMessage logOptions (Message level message pairs zonedTime)
+
+step :: ( Member (Env address) effects
+        , Member (Exc SomeException) effects
+        , Member REPL effects
+        , Member (Reader ModuleInfo) effects
+        , Member (Reader Span) effects
+        , Member (Reader Step) effects
+        , Member (State [Breakpoint]) effects
+        , Show address
+        )
+     => [(ModulePath, Blob)]
+     -> SubtermAlgebra (Base term) term (TermEvaluator term address value effects a)
+     -> SubtermAlgebra (Base term) term (TermEvaluator term address value effects a)
+step blobs recur term = do
+  break <- shouldBreak
+  if break then do
+    list
+    runCommands (recur term)
+  else
+    recur term
+  where list = do
+          path <- asks modulePath
+          span <- ask
+          maybe (pure ()) (\ blob -> output (showExcerpt True span blob "")) (Prelude.lookup path blobs)
+        help = do
+          output "Commands available from the prompt:"
+          output ""
+          output "  :help, :?                   display this list of commands"
+          output "  :list                       show the source code around current breakpoint"
+          output "  :step                       single-step after stopping at a breakpoint"
+          output "  :continue                   continue evaluation until the next breakpoint"
+          output "  :show bindings              show the current bindings"
+          output "  :quit, :q, :abandon         abandon the current evaluation and exit the repl"
+        showBindings = do
+          bindings <- Env.head <$> TermEvaluator getEnv
+          output $ unlines (uncurry showBinding <$> Env.pairs bindings)
+        showBinding name addr = show name <> " = " <> show addr
+        runCommand run [":step"]     = local (const Step) run
+        runCommand run [":continue"] = local (const Continue) run
+        runCommand run [":break", s]
+          | [(i, "")] <- readDec s = modify' (OnLine i :) >> runCommands run
+        -- TODO: :show breakpoints
+        -- TODO: :delete breakpoints
+        runCommand run [":list"] = list >> runCommands run
+        runCommand run [":show", "bindings"] = showBindings >> runCommands run
+        -- TODO: show the value(s) in the heap
+        -- TODO: can we call functions somehow? Maybe parse expressions with the current parser?
+        runCommand _   [quit] | quit `elem` [":quit", ":q", ":abandon"] = throwError (SomeException Quit)
+        runCommand run [":help"] = help >> runCommands run
+        runCommand run [":?"] = help >> runCommands run
+        runCommand run [] = runCommands run
+        runCommand run other = output ("unknown command '" <> unwords other <> "'") >> output "use :? for help" >> runCommands run
+        runCommands run = do
+          str <- prompt
+          maybe (runCommands run) (runCommand run . words) str
+
+
+newtype Breakpoint
+  = OnLine Int
+  deriving Show
+
+-- FIXME: OnLine should take a module, defaulting to the current module
+-- TODO: OnPos, taking a column number as well as line number and module
+-- TODO: OnSymbol, taking a function/method name? This could be tricky to implement cross-language
+
+data Step
+  = Step
+  | Continue
+  deriving Show
+
+-- TODO: StepLocal/StepModule
+
+shouldBreak :: (Member (State [Breakpoint]) effects, Member (Reader Span) effects, Member (Reader Step) effects) => TermEvaluator term address value effects Bool
+shouldBreak = do
+  step <- ask
+  case step of
+    Step -> pure True
+    Continue -> do
+      breakpoints <- get
+      span <- ask
+      pure (any @[] (matching span) breakpoints)
+  where matching Span{..} (OnLine n)
+          | n >= posLine spanStart
+          , n <= posLine spanEnd   = True
+          | otherwise              = False
+
+
+cyan :: String
+cyan = "\ESC[1;36m\STX"
+
+plain :: String
+plain = "\ESC[0m\STX"
--- a/src/Semantic/Task.hs
+++ b/src/Semantic/Task.hs
@ -39,6 +39,8 @@ module Semantic.Task
 , runTaskWithOptions
 , withOptions
 , runTaskWithConfig
+, runTraceInTelemetry
+, runTaskF
 -- * Re-exports
 , Distribute
 , Eff
--- a/src/Semantic/Telemetry.hs
+++ b/src/Semantic/Telemetry.hs
@ -42,7 +42,7 @@ module Semantic.Telemetry
 , writeLog
 , writeStat
 , time
-, Telemetry
+, Telemetry(..)
 , runTelemetry
 , ignoreTelemetry
 ) where
--- a/src/Semantic/Util.hs
+++ b/src/Semantic/Util.hs
@ -14,7 +14,6 @@ import           Control.Exception (displayException)
 import           Control.Monad.Effect.Trace (runPrintingTrace)
 import           Data.Abstract.Address.Monovariant as Monovariant
 import           Data.Abstract.Address.Precise as Precise
-import           Data.Abstract.BaseError (BaseError (..))
 import           Data.Abstract.Evaluatable
 import           Data.Abstract.Module
 import qualified Data.Abstract.ModuleTable as ModuleTable
@ -56,9 +55,9 @@ import           Text.Show.Pretty (ppShow)

 justEvaluating
  = runM
+  . runPrintingTrace
  . runState lowerBound
  . runFresh 0
-  . runPrintingTrace
  . fmap reassociate
  . runLoadError
  . runUnspecialized
@ -68,37 +67,11 @@ justEvaluating
  . runAddressError
  . runValueError

-newtype UtilEff a = UtilEff
-  { runUtilEff :: Eff '[ Function Precise (Value Precise UtilEff)
-                       , Exc (LoopControl Precise)
-                       , Exc (Return Precise)
-                       , Env Precise
-                       , Deref (Value Precise UtilEff)
-                       , Allocator Precise
-                       , Reader ModuleInfo
-                       , Modules Precise
-                       , Reader (ModuleTable (NonEmpty (Module (ModuleResult Precise))))
-                       , Reader Span
-                       , Reader PackageInfo
-                       , Resumable (BaseError (ValueError Precise UtilEff))
-                       , Resumable (BaseError (AddressError Precise (Value Precise UtilEff)))
-                       , Resumable (BaseError ResolutionError)
-                       , Resumable (BaseError EvalError)
-                       , Resumable (BaseError (EnvironmentError Precise))
-                       , Resumable (BaseError (UnspecializedError (Value Precise UtilEff)))
-                       , Resumable (BaseError (LoadError Precise))
-                       , Trace
-                       , Fresh
-                       , State (Heap Precise (Value Precise UtilEff))
-                       , Lift IO
-                       ] a
-  }
-
 checking
  = runM @_ @IO
+  . runPrintingTrace
  . runState (lowerBound @(Heap Monovariant Type))
  . runFresh 0
-  . runPrintingTrace
  . runTermEvaluator @_ @Monovariant @Type
  . caching
  . providingLiveSet
@ -112,7 +85,7 @@ checking
  . runTypes

 evalGoProject         = justEvaluating <=< evaluateProject (Proxy :: Proxy 'Language.Go)         goParser
-evalRubyProject       = justEvaluating <=< evaluateProject (Proxy :: Proxy 'Language.Ruby)       rubyParser
+evalRubyProject       = justEvaluating <=< evaluateProject (Proxy @'Language.Ruby)       rubyParser
 evalPHPProject        = justEvaluating <=< evaluateProject (Proxy :: Proxy 'Language.PHP)        phpParser
 evalPythonProject     = justEvaluating <=< evaluateProject (Proxy :: Proxy 'Language.Python)     pythonParser
 evalJavaScriptProject = justEvaluating <=< evaluateProject (Proxy :: Proxy 'Language.JavaScript) typescriptParser
@ -123,7 +96,7 @@ typecheckRubyFile = checking <=< evaluateProjectWithCaching (Proxy :: Proxy 'Lan

 callGraphProject parser proxy opts paths = runTaskWithOptions opts $ do
  blobs <- catMaybes <$> traverse readFile (flip File (Language.reflect proxy) <$> paths)
-  package <- parsePackage parser (Project (takeDirectory (maybe "/" fst (uncons paths))) blobs (Language.reflect proxy) [])
+  package <- fmap snd <$> parsePackage parser (Project (takeDirectory (maybe "/" fst (uncons paths))) blobs (Language.reflect proxy) [])
  modules <- topologicalSort <$> runImportGraphToModules proxy package
  x <- runCallGraph proxy False modules package
  pure (x, (() <$) <$> modules)
@ -139,20 +112,20 @@ data TaskConfig = TaskConfig Config LogQueue StatQueue

 evaluateProject' (TaskConfig config logger statter) proxy parser paths = either (die . displayException) pure <=< runTaskWithConfig config logger statter $ do
  blobs <- catMaybes <$> traverse readFile (flip File (Language.reflect proxy) <$> paths)
-  package <- fmap quieterm <$> parsePackage parser (Project (takeDirectory (maybe "/" fst (uncons paths))) blobs (Language.reflect proxy) [])
+  package <- fmap (quieterm . snd) <$> parsePackage parser (Project (takeDirectory (maybe "/" fst (uncons paths))) blobs (Language.reflect proxy) [])
  modules <- topologicalSort <$> runImportGraphToModules proxy package
  trace $ "evaluating with load order: " <> show (map (modulePath . moduleInfo) modules)
-  pure (runTermEvaluator @_ @_ @(Value Precise UtilEff)
-       (runReader (packageInfo package)
-       (runReader (lowerBound @Span)
+  pure (runTermEvaluator @_ @_ @(Value Precise (ConcreteEff Precise _))
       (runReader (lowerBound @(ModuleTable (NonEmpty (Module (ModuleResult Precise)))))
       (raiseHandler (runModules (ModuleTable.modulePaths (packageModules package)))
+       (runReader (packageInfo package)
+       (runReader (lowerBound @Span)
       (evaluate proxy id withTermSpans (Precise.runAllocator . Precise.runDeref) (Concrete.runFunction coerce coerce) modules))))))


 evaluateProjectWithCaching proxy parser path = runTaskWithOptions debugOptions $ do
  project <- readProject Nothing path (Language.reflect proxy) []
-  package <- fmap quieterm <$> parsePackage parser project
+  package <- fmap (quieterm . snd) <$> parsePackage parser project
  modules <- topologicalSort <$> runImportGraphToModules proxy package
  pure (runReader (packageInfo package)
       (runReader (lowerBound @Span)
--- a/test/Control/Abstract/Evaluator/Spec.hs
+++ b/test/Control/Abstract/Evaluator/Spec.hs
@ -1,7 +1,6 @@
 {-# LANGUAGE TypeOperators #-}
 module Control.Abstract.Evaluator.Spec
 ( spec
-, SpecEff(..)
 ) where

 import Control.Abstract
--- a/test/Data/Functor/Listable.hs
+++ b/test/Data/Functor/Listable.hs
@ -11,18 +11,7 @@ module Data.Functor.Listable
 , cons5
 , cons6
 , (\/)
-, Tier
-, Listable1(..)
-, tiers1
-, Listable2(..)
-, tiers2
-, liftCons1
-, liftCons2
-, liftCons3
-, liftCons4
-, liftCons5
 , ListableF(..)
-, ListableF2(..)
 , addWeight
 , ofWeight
 , ListableSyntax
--- a/test/Graphing/Calls/Spec.hs
+++ b/test/Graphing/Calls/Spec.hs
@ -22,7 +22,7 @@ callGraphPythonProject paths = runTaskWithOptions defaultOptions $ do
  let proxy = Proxy @'Language.Python
  let lang = Language.Python
  blobs <- catMaybes <$> traverse readFile (flip File lang <$> paths)
-  package <- parsePackage pythonParser (Project (takeDirectory (maybe "/" fst (uncons paths))) blobs lang [])
+  package <- fmap snd <$> parsePackage pythonParser (Project (takeDirectory (maybe "/" fst (uncons paths))) blobs lang [])
  modules <- topologicalSort <$> runImportGraphToModules proxy package
  runCallGraph proxy False modules package

--- a/test/SpecHelpers.hs
+++ b/test/SpecHelpers.hs
@ -73,6 +73,7 @@ import qualified Data.ByteString as B
 import qualified Data.Set as Set
 import qualified Semantic.IO as IO
 import Semantic.Config (Config)
+import Semantic.Graph (ConcreteEff)
 import Semantic.Telemetry (LogQueue, StatQueue)
 import System.Exit (die)
 import Control.Exception (displayException)
@ -97,19 +98,19 @@ readFilePair :: Both FilePath -> IO BlobPair
 readFilePair paths = let paths' = fmap file paths in
                     runBothWith IO.readFilePair paths'

-type TestEvaluatingEffects = '[ Resumable (BaseError (ValueError Precise UtilEff))
+type TestEvaluatingEffects = '[ Resumable (BaseError (ValueError Precise (ConcreteEff Precise '[Trace, Lift IO])))
                              , Resumable (BaseError (AddressError Precise Val))
                              , Resumable (BaseError ResolutionError)
                              , Resumable (BaseError EvalError)
                              , Resumable (BaseError (EnvironmentError Precise))
                              , Resumable (BaseError (UnspecializedError Val))
                              , Resumable (BaseError (LoadError Precise))
-                              , Trace
                              , Fresh
                              , State (Heap Precise Val)
+                              , Trace
                              , Lift IO
                              ]
-type TestEvaluatingErrors = '[ BaseError (ValueError Precise UtilEff)
+type TestEvaluatingErrors = '[ BaseError (ValueError Precise (ConcreteEff Precise '[Trace, Lift IO]))
                             , BaseError (AddressError Precise Val)
                             , BaseError ResolutionError
                             , BaseError EvalError
@ -127,10 +128,9 @@ testEvaluating :: Evaluator Precise Val TestEvaluatingEffects (ModuleTable (NonE
                 )
 testEvaluating
  = runM
-  . fmap (\ (heap, (traces, res)) -> (traces, (heap, res)))
+  . runReturningTrace
  . runState lowerBound
  . runFresh 0
-  . runReturningTrace
  . fmap reassociate
  . runLoadError
  . runUnspecialized
@ -138,9 +138,9 @@ testEvaluating
  . runEvalError
  . runResolutionError
  . runAddressError
-  . runValueError @_ @Precise @UtilEff
+  . runValueError @_ @Precise @(ConcreteEff Precise _)

-type Val = Value Precise UtilEff
+type Val = Value Precise (ConcreteEff Precise '[Trace, Lift IO])


 deNamespace :: Heap Precise (Value Precise term)