Map Implementation (#1222)

distribution/bin/enso

@@ -1,3 +1,3 @@
 COMP_PATH=$(dirname "$0")/../component
-exec java -jar -Dtruffle.class.path.append="$COMP_PATH/runtime.jar" -Dpolyglot.engine.IterativePartialEscape=true $JAVA_OPTS $COMP_PATH/runner.jar "$@"
+exec java -jar -Dtruffle.class.path.append="$COMP_PATH/runtime.jar" $JAVA_OPTS $COMP_PATH/runner.jar "$@"
 exit

distribution/std-lib/Base/src/Data/Map.enso

@@ -0,0 +1,79 @@
+from Base import all
+import Base.Data.Map.Internal
+
+## An error for getting a missing value from a map.
+type No_Value_For_Key key
+
+## A key-value store. This type assumes all keys are pairwise comparable,
+   using the `<`, `>` and `==` operators.
+type Map
+    type Tip
+    type Bin s key value left right
+
+    ## Checks if the map is empty.
+    is_empty : Boolean
+    is_empty = case this of
+        Bin _ _ _ _ _ -> False
+        Tip -> True
+
+    ## Returns the number of entries in this map.
+    size : Integer
+    size = case this of
+        Bin s _ _ _ _ -> s
+        Tip -> 0
+
+    ## Converts the map into a vector of `[key, value]` pairs.
+       The returned vector is sorted in the increasing order of keys.
+    to_vector : Vector
+    to_vector =
+        builder = Vector.new_builder
+        to_vector_with_builder m = case m of
+            Bin _ k v l r ->
+                to_vector_with_builder l
+                builder.append [k, v]
+                to_vector_with_builder r
+                Unit
+            Tip -> Unit
+        to_vector_with_builder this
+        result = builder.to_vector
+        result
+
+    ## Returns a text representation of this map.
+    to_text : Text
+    to_text = this.to_vector.to_text
+
+    ## Checks if this map is equal to another map.
+
+       Maps are equal when they contained the same keys and the values
+       associated with each key are pairwise equal.
+    == : Map -> Boolean
+    == that = this.to_vector == that.to_vector
+
+    ## Maps a function over each value in this map.
+    map : (Any -> Any) -> Map
+    map function = case this of
+        Bin s k v l r ->
+            Bin s k (function v) (l.map function) (r.map function)
+        Tip -> Tip
+
+    ## Gets the value associated with `key` in this map, or returns a
+       `No_Value_For_Key` error, if `key` is not present.
+    get : Any -> Any ! No_Value_For_Key
+    get key =
+        go map = case map of
+            Tip -> Error.throw (No_Value_For_Key key)
+            Bin _ k v l r ->
+                if k == key then v else
+                    if k > key then @Tail_Call go l else @Tail_Call go r
+        result = go this
+        result
+
+    ## Inserts a key-value mapping into this map. If `key` is already present,
+       it will be overriden with the new `value`.
+    insert : Any -> Any -> Map
+    insert key value = Internal.insert this key value
+
+## Returns an empty map.
+empty : Map
+empty = Tip
+

distribution/std-lib/Base/src/Data/Map/Internal.enso

@@ -0,0 +1,113 @@
+from Base import all
+from Base.Data.Map import all
+
+## PRIVATE
+
+   Helper used in the insert operation.
+insert_l key value k v l r =
+    new_left = here.insert l key value
+    here.balance_left k v new_left r
+
+## PRIVATE
+
+   Helper used in the insert operation.
+insert_r key value k v l r =
+    new_right = here.insert r key value
+    here.balance_right k v l new_right
+
+## PRIVATE
+
+   Helper for inserting a new key-value pair into a map.
+
+   The algorithm used here is based on the paper "Implementing Sets Efficiently
+   in a Functional Language" by Stephen Adams.
+   Implementation is based on Haskell's `Data.Map.Strict` implemented in the
+   `containers` package.
+insert map key value = case map of
+    Bin s k v l r ->
+        if key > k then @Tail_Call here.insert_r key value k v l r else
+            if key == k then @Tail_Call Bin s k value l r else
+                @Tail_Call here.insert_l key value k v l r
+    _ -> Bin 1 key value Tip Tip
+
+## PRIVATE
+
+   Rebalances the map after the left subtree grows.
+balance_left k x l r = case r of
+    Bin rs _ _ _ _ -> case l of
+        Bin ls lk lx ll lr ->
+            if ls <= Delta*rs then Bin 1+ls+rs k x l r else
+                lls = here.size ll
+                case lr of
+                    Bin lrs lrk lrx lrl lrr ->
+                        if lrs < Ratio*lls then Bin 1+ls+rs lk lx ll (Bin 1+rs+lrs k x lr r) else
+                            lrls = here.size lrl
+                            lrrs = here.size lrr
+                            Bin 1+ls+rs lrk lrx (Bin 1+lls+lrls lk lx ll lrl) (Bin 1+rs+lrrs k x lrr r)
+        _ -> Bin 1+rs k x Tip r
+    _ -> case l of
+        Tip -> Bin 1 k x Tip Tip
+        Bin _ _ _ Tip Tip -> Bin 2 k x l Tip
+        Bin _ lk lx Tip (Bin _ lrk lrx _ _) -> Bin 3 lrk lrx (Bin 1 lk lx Tip Tip) (Bin 1 k x Tip Tip)
+        Bin _ lk lx ll Tip -> Bin 3 lk lx ll (Bin 1 k x Tip Tip)
+        Bin ls lk lx ll lr -> case lr of
+            Bin lrs lrk lrx lrl lrr ->
+                lls = here.size ll
+                if lrs < Ratio*lls then Bin 1+ls lk lx ll (Bin 1+lrs k x lr Tip) else
+                    lrls = here.size lrl
+                    lrrs = here.size lrr
+                    Bin 1+ls lrk lrx (Bin 1+lls+lrls lk lx ll lrl) (Bin 1+lrrs k x lrr Tip)
+
+## PRIVATE
+
+   Rebalances the map after the right subtree grows.
+balance_right k x l r = case l of
+    Bin ls _ _ _ _ -> case r of
+        Bin rs rk rx rl rr ->
+            if rs <= Delta*ls then Bin 1+ls+rs k x l r else
+                case rl of
+                    Bin rls rlk rlx rll rlr ->
+                        rrs = here.size rr
+                        if rls < Ratio*rrs then Bin 1+ls+rs rk rx (Bin 1+ls+rls k x l rl) rr else
+                            rlls = here.size rll
+                            rlrs = here.size rlr
+                            Bin 1+ls+rs rlk rlx (Bin 1+ls+rlls k x l rll) (Bin 1+rrs+rlrs rk rx rlr rr)
+        _ -> Bin 1+ls k x l Tip
+    _ -> case r of
+        Tip -> Bin 1 k x Tip Tip
+        Bin _ _ _ Tip Tip -> Bin 2 k x Tip r
+        Bin _ rk rx Tip rr -> Bin 3 rk rx (Bin 1 k x Tip Tip) rr
+        Bin _ rk rx (Bin _ rlk rlx _ _) Tip -> Bin 3 rlk rlx (Bin 1 k x Tip Tip) (Bin 1 rk rx Tip Tip)
+        Bin rs rk rx (Bin rls rlk rlx rll rlr) rr -> case rr of
+            Bin rrs _ _ _ _ ->
+                if rls < Ratio*rrs then Bin 1+rs rk rx (Bin 1+rls k x Tip rl) rr else
+                    srll = here.size rll
+                    srlr = here.size rlr
+                    Bin 1+rs rlk rlx (Bin 1+srll k x Tip rll) (Bin 1+rrs+srlr rk rx rlr rr)
+
+## PRIVATE
+
+   Controls the difference between inner and outer siblings of a heavy subtree.
+   Used to decide between a double and a single rotation.
+
+   The choice of values for `ratio` and `delta` is taken from the Haskell
+   implementation.
+ratio : Integer
+ratio = 2
+
+## PRIVATE
+
+   Controls the maximum size difference between subtrees.
+
+   The choice of values for `ratio` and `delta` is taken from the Haskell
+   implementation.
+delta : Integer
+delta = 3
+
+## PRIVATE
+
+   Gets the size of a map.
+size m = case m of
+    Bin s _ _ _ _ -> s
+    _ -> 0
+

distribution/std-lib/Base/src/Main.enso

@@ -7,11 +7,13 @@ import Base.Meta.Enso_Project
 import Base.Meta.Meta
 import Base.Error.Extensions
 import Base.Polyglot.Java
+import Base.Data.Map
 from Builtins import Unit, Number, Integer, Any, True, False, Cons
 
 export Base.Meta.Meta
 from Builtins export all hiding Meta
 
+export Base.Data.Map
 from Base.Meta.Enso_Project export all
 from Base.List export Nil, Cons
 from Base.Vector export Vector

distribution/std-lib/Base/src/Test.enso

@@ -38,7 +38,7 @@ type Verbs
 
     equal subject argument =
         if subject == argument then Success else
-            msg = this.to_text + " did not equal " + that.to_text + "."
+            msg = this.to_text + " did not equal " + argument.to_text + "."
             here.fail msg
 
     be subject argument = this.equal subject argument

distribution/std-lib/Base/src/Text/Extensions.enso

@@ -69,6 +69,14 @@ Text.split_at separator =
 Text.== : Text -> Boolean
 Text.== that = Text_Utils.equals [this, that]
 
+## Checks if `this` is lexicographically before `that`.
+Text.< : Text -> Boolean
+Text.< that = Text_Utils.lt [this, that]
+
+## Checks if `this` is lexicographically after `that`.
+Text.> : Text -> Boolean
+Text.> that = Text_Utils.lt [that, this]
+
 ## Returns a vector containing bytes representing the UTF-8 encoding of the
    input text.
 
@@ -103,4 +111,5 @@ Text.from_codepoints : Vector -> Text
 Text.from_codepoints codepoints = Text_Utils.from_codepoints [codepoints.to_array]
 
 ## Checks whether `this` starts with `prefix`.
+Text.starts_with : Text -> Boolean
 Text.starts_with prefix = Text_Utils.starts_with [this, prefix]

engine/runtime/src/bench/java/org/enso/interpreter/bench/benchmarks/semantic/RecursionBenchmarks.java

@@ -1,17 +1,10 @@
 package org.enso.interpreter.bench.benchmarks.semantic;
 
-import java.util.ArrayDeque;
-import java.util.Deque;
-import java.util.concurrent.TimeUnit;
 import org.enso.interpreter.bench.fixtures.semantic.RecursionFixtures;
 import org.enso.interpreter.test.DefaultInterpreterRunner;
-import org.openjdk.jmh.annotations.Benchmark;
-import org.openjdk.jmh.annotations.BenchmarkMode;
-import org.openjdk.jmh.annotations.Fork;
-import org.openjdk.jmh.annotations.Measurement;
-import org.openjdk.jmh.annotations.Mode;
-import org.openjdk.jmh.annotations.OutputTimeUnit;
-import org.openjdk.jmh.annotations.Warmup;
+import org.openjdk.jmh.annotations.*;
+
+import java.util.concurrent.TimeUnit;
 
 @BenchmarkMode(Mode.AverageTime)
 @Fork(1)

engine/runtime/src/main/java/org/enso/interpreter/node/callable/IndirectInvokeCallableNode.java

@@ -119,7 +119,7 @@ public abstract class IndirectInvokeCallableNode extends Node {
       Object selfArgument = arguments[thisArgumentPosition];
       if (argumentsExecutionMode.shouldExecute()) {
         Stateful selfResult =
-            thisExecutor.executeThunk((Thunk) selfArgument, state, BaseNode.TailStatus.NOT_TAIL);
+            thisExecutor.executeThunk(selfArgument, state, BaseNode.TailStatus.NOT_TAIL);
         selfArgument = selfResult.getValue();
         state = selfResult.getState();
         arguments[thisArgumentPosition] = selfArgument;

engine/runtime/src/main/java/org/enso/interpreter/node/callable/InvokeCallableNode.java

@@ -185,8 +185,7 @@ public abstract class InvokeCallableNode extends BaseNode {
             lock.unlock();
           }
         }
-        Stateful selfResult =
-            thisExecutor.executeThunk((Thunk) selfArgument, state, TailStatus.NOT_TAIL);
+        Stateful selfResult = thisExecutor.executeThunk(selfArgument, state, TailStatus.NOT_TAIL);
         selfArgument = selfResult.getValue();
         state = selfResult.getState();
         arguments[thisArgumentPosition] = selfArgument;

engine/runtime/src/main/java/org/enso/interpreter/node/callable/argument/ArgumentSorterNode.java

@@ -55,11 +55,11 @@ public class ArgumentSorterNode extends BaseNode {
         preApplicationSchema, mapping.getPostApplicationSchema(), mapping, argumentsExecutionMode);
   }
 
-  private void initArgumentExecutors(Object[] arguments) {
+  private void initArgumentExecutors() {
     ThunkExecutorNode[] executors =
         new ThunkExecutorNode[mapping.getArgumentShouldExecute().length];
     for (int i = 0; i < mapping.getArgumentShouldExecute().length; i++) {
-      if (mapping.getArgumentShouldExecute()[i] && TypesGen.isThunk(arguments[i])) {
+      if (mapping.getArgumentShouldExecute()[i]) {
         executors[i] = insert(ThunkExecutorNode.build());
       }
     }
@@ -74,7 +74,7 @@ public class ArgumentSorterNode extends BaseNode {
       lock.lock();
       try {
         if (executors == null) {
-          initArgumentExecutors(arguments);
+          initArgumentExecutors();
         }
       } finally {
         lock.unlock();
@@ -82,8 +82,7 @@ public class ArgumentSorterNode extends BaseNode {
     }
     for (int i = 0; i < mapping.getArgumentShouldExecute().length; i++) {
       if (executors[i] != null) {
-        Stateful result =
-            executors[i].executeThunk(TypesGen.asThunk(arguments[i]), state, TailStatus.NOT_TAIL);
+        Stateful result = executors[i].executeThunk(arguments[i], state, TailStatus.NOT_TAIL);
         arguments[i] = result.getValue();
         state = result.getState();
       }

engine/runtime/src/main/java/org/enso/interpreter/node/callable/thunk/ForceNode.java

@@ -30,7 +30,7 @@ public abstract class ForceNode extends ExpressionNode {
   @Specialization
   Object passToExecutorNode(
       VirtualFrame frame,
-      Thunk thunk,
+      Object thunk,
       @Cached("build()") ThunkExecutorNode thunkExecutorNode) {
     Object state = FrameUtil.getObjectSafe(frame, getStateFrameSlot());
     Stateful result = thunkExecutorNode.executeThunk(thunk, state, getTailStatus());

engine/runtime/src/main/java/org/enso/interpreter/node/callable/thunk/ThunkExecutorNode.java

@@ -12,6 +12,7 @@ import org.enso.interpreter.runtime.callable.argument.Thunk;
 import org.enso.interpreter.runtime.callable.function.Function;
 import org.enso.interpreter.runtime.control.TailCallException;
 import org.enso.interpreter.runtime.state.Stateful;
+import org.enso.interpreter.runtime.type.TypesGen;
 
 /** Node responsible for executing (forcing) thunks passed to it as runtime values. */
 @GenerateUncached
@@ -37,7 +38,16 @@ public abstract class ThunkExecutorNode extends Node {
    * @param isTail is the execution happening in a tail-call position
    * @return the return value of this thunk
    */
-  public abstract Stateful executeThunk(Thunk thunk, Object state, BaseNode.TailStatus isTail);
+  public abstract Stateful executeThunk(Object thunk, Object state, BaseNode.TailStatus isTail);
+
+  static boolean isThunk(Object th) {
+    return TypesGen.isThunk(th);
+  }
+
+  @Specialization(guards = "!isThunk(thunk)")
+  Stateful doOther(Object thunk, Object state, BaseNode.TailStatus isTail) {
+    return new Stateful(state, thunk);
+  }
 
   @Specialization(
       guards = "callNode.getCallTarget() == thunk.getCallTarget()",

engine/runtime/src/main/java/org/enso/interpreter/node/controlflow/BooleanBranchNode.java

@@ -1,9 +1,11 @@
 package org.enso.interpreter.node.controlflow;
 
+import com.oracle.truffle.api.RootCallTarget;
 import com.oracle.truffle.api.dsl.Fallback;
 import com.oracle.truffle.api.dsl.Specialization;
 import com.oracle.truffle.api.frame.FrameUtil;
 import com.oracle.truffle.api.frame.VirtualFrame;
+import com.oracle.truffle.api.nodes.DirectCallNode;
 import com.oracle.truffle.api.nodes.NodeInfo;
 import com.oracle.truffle.api.profiles.ConditionProfile;
 import org.enso.interpreter.node.ExpressionNode;
@@ -13,19 +15,19 @@ import org.enso.interpreter.node.callable.function.CreateFunctionNode;
 import org.enso.interpreter.runtime.callable.atom.Atom;
 import org.enso.interpreter.runtime.callable.atom.AtomConstructor;
 import org.enso.interpreter.runtime.callable.function.Function;
+import org.enso.interpreter.runtime.state.Stateful;
 import org.enso.interpreter.runtime.type.TypesGen;
 
 /** An implementation of the case expression specialised to working on booleans. */
 @NodeInfo(shortName = "BooleanMatch")
 public abstract class BooleanBranchNode extends BranchNode {
   private final boolean matched;
-  private @Child ExpressionNode branch;
-  private @Child ExecuteCallNode executeCallNode = ExecuteCallNodeGen.create();
   private final ConditionProfile profile = ConditionProfile.createCountingProfile();
+  private @Child DirectCallNode callNode;
 
-  BooleanBranchNode(boolean matched, CreateFunctionNode branch) {
+  BooleanBranchNode(boolean matched, RootCallTarget branch) {
     this.matched = matched;
-    this.branch = branch;
+    this.callNode = DirectCallNode.create(branch);
   }
 
   /**
@@ -35,7 +37,7 @@ public abstract class BooleanBranchNode extends BranchNode {
    * @param branch the expression to be executed if (@code matcher} matches
    * @return a node for matching in a case expression
    */
-  public static BooleanBranchNode build(boolean matched, CreateFunctionNode branch) {
+  public static BooleanBranchNode build(boolean matched, RootCallTarget branch) {
     return BooleanBranchNodeGen.create(matched, branch);
   }
 
@@ -43,17 +45,19 @@ public abstract class BooleanBranchNode extends BranchNode {
    * Handles the boolean scrutinee case.
    *
    * @param frame the stack frame in which to execute
+   * @param state current monadic state
    * @param target the atom to destructure
    */
   @Specialization
-  public void doAtom(VirtualFrame frame, boolean target) {
-    Object state = FrameUtil.getObjectSafe(frame, getStateFrameSlot());
+  public void doAtom(VirtualFrame frame, Object state, boolean target) {
     if (profile.profile(matched == target)) {
-      Function function = TypesGen.asFunction(branch.executeGeneric(frame));
-
+      Stateful result =
+          (Stateful)
+              callNode.call(
+                  Function.ArgumentsHelper.buildArguments(
+                      frame.materialize(), state, new Object[0]));
       // Note [Caller Info For Case Branches]
-      throw new BranchSelectedException(
-          executeCallNode.executeCall(function, null, state, new Object[0]));
+      throw new BranchSelectedException(result);
     }
   }
 
@@ -64,7 +68,7 @@ public abstract class BooleanBranchNode extends BranchNode {
    * @param target the object to execute on
    */
   @Fallback
-  public void doFallback(VirtualFrame frame, Object target) {}
+  public void doFallback(VirtualFrame frame, Object state, Object target) {}
 
   /* Note [Caller Info For Case Branches]
    * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

engine/runtime/src/main/java/org/enso/interpreter/node/controlflow/BranchNode.java

@@ -15,7 +15,8 @@ public abstract class BranchNode extends BaseNode {
    * Executes the case branch.
    *
    * @param frame the stack frame in which to execute
+   * @param state current monadic state
    * @param target the object to match against
    */
-  public abstract void execute(VirtualFrame frame, Object target);
+  public abstract void execute(VirtualFrame frame, Object state, Object target);
 }

engine/runtime/src/main/java/org/enso/interpreter/node/controlflow/CaseNode.java

@@ -3,13 +3,12 @@ package org.enso.interpreter.node.controlflow;
 import com.oracle.truffle.api.CompilerDirectives;
 import com.oracle.truffle.api.TruffleLanguage;
 import com.oracle.truffle.api.dsl.CachedContext;
-import com.oracle.truffle.api.dsl.ImportStatic;
 import com.oracle.truffle.api.dsl.NodeChild;
 import com.oracle.truffle.api.dsl.Specialization;
+import com.oracle.truffle.api.frame.FrameUtil;
 import com.oracle.truffle.api.frame.VirtualFrame;
 import com.oracle.truffle.api.nodes.ExplodeLoop;
 import com.oracle.truffle.api.nodes.NodeInfo;
-import com.oracle.truffle.api.profiles.BranchProfile;
 import org.enso.interpreter.Language;
 import org.enso.interpreter.node.ExpressionNode;
 import org.enso.interpreter.runtime.Context;
@@ -29,7 +28,6 @@ import org.enso.interpreter.runtime.type.TypesGen;
 public abstract class CaseNode extends ExpressionNode {
 
   @Children private final BranchNode[] cases;
-  private final BranchProfile typeErrorProfile = BranchProfile.create();
 
   CaseNode(BranchNode[] cases) {
     this.cases = cases;
@@ -74,9 +72,10 @@ public abstract class CaseNode extends ExpressionNode {
       VirtualFrame frame,
       Object object,
       @CachedContext(Language.class) TruffleLanguage.ContextReference<Context> ctx) {
+    Object state = FrameUtil.getObjectSafe(frame, getStateFrameSlot());
     try {
       for (BranchNode branchNode : cases) {
-        branchNode.execute(frame, object);
+        branchNode.execute(frame, state, object);
       }
       CompilerDirectives.transferToInterpreter();
       throw new PanicException(

engine/runtime/src/main/java/org/enso/interpreter/node/controlflow/CatchAllBranchNode.java

@@ -1,15 +1,19 @@
 package org.enso.interpreter.node.controlflow;
 
+import com.oracle.truffle.api.RootCallTarget;
 import com.oracle.truffle.api.frame.FrameUtil;
 import com.oracle.truffle.api.frame.VirtualFrame;
+import com.oracle.truffle.api.nodes.DirectCallNode;
 import com.oracle.truffle.api.nodes.NodeInfo;
 import com.oracle.truffle.api.nodes.UnexpectedResultException;
+import com.oracle.truffle.api.profiles.ConditionProfile;
 import org.enso.interpreter.node.ExpressionNode;
 import org.enso.interpreter.node.callable.ExecuteCallNode;
 import org.enso.interpreter.node.callable.ExecuteCallNodeGen;
 import org.enso.interpreter.node.callable.function.CreateFunctionNode;
 import org.enso.interpreter.runtime.callable.atom.Atom;
 import org.enso.interpreter.runtime.callable.function.Function;
+import org.enso.interpreter.runtime.state.Stateful;
 import org.enso.interpreter.runtime.type.TypesGen;
 
 /**
@@ -20,11 +24,10 @@ import org.enso.interpreter.runtime.type.TypesGen;
     shortName = "Catch_All",
     description = "An explicit catch-all branch in a case expression")
 public class CatchAllBranchNode extends BranchNode {
-  @Child private ExpressionNode functionNode;
-  @Child private ExecuteCallNode executeCallNode = ExecuteCallNodeGen.create();
+  private @Child DirectCallNode callNode;
 
-  private CatchAllBranchNode(CreateFunctionNode functionNode) {
-    this.functionNode = functionNode;
+  private CatchAllBranchNode(RootCallTarget functionNode) {
+    this.callNode = DirectCallNode.create(functionNode);
   }
 
   /**
@@ -33,7 +36,7 @@ public class CatchAllBranchNode extends BranchNode {
    * @param functionNode the function to execute in this case
    * @return a catch-all node
    */
-  public static CatchAllBranchNode build(CreateFunctionNode functionNode) {
+  public static CatchAllBranchNode build(RootCallTarget functionNode) {
     return new CatchAllBranchNode(functionNode);
   }
 
@@ -41,15 +44,17 @@ public class CatchAllBranchNode extends BranchNode {
    * Executes the case branch on an arbitrary target.
    *
    * @param frame the stack frame in which to execute
+   * @param state current monadic state
    * @param target the object to match against
    */
-  public void execute(VirtualFrame frame, Object target) {
+  public void execute(VirtualFrame frame, Object state, Object target) {
     // Note [Safe Casting to Function in Catch All Branches]
-    Function function = TypesGen.asFunction(functionNode.executeGeneric(frame));
-    Object state = FrameUtil.getObjectSafe(frame, getStateFrameSlot());
-    throw new BranchSelectedException(
-        // Note [Caller Info For Case Branches]
-        executeCallNode.executeCall(function, null, state, new Object[] {target}));
+    Stateful result =
+        (Stateful)
+            callNode.call(
+                Function.ArgumentsHelper.buildArguments(
+                    frame.materialize(), state, new Object[] {target}));
+    throw new BranchSelectedException(result);
   }
 
   /* Note [Safe Casting to Function in Catch All Branches]

engine/runtime/src/main/java/org/enso/interpreter/node/controlflow/ConstructorBranchNode.java

@@ -1,11 +1,16 @@
 package org.enso.interpreter.node.controlflow;
 
+import com.oracle.truffle.api.CompilerDirectives;
+import com.oracle.truffle.api.RootCallTarget;
 import com.oracle.truffle.api.dsl.Fallback;
 import com.oracle.truffle.api.dsl.Specialization;
 import com.oracle.truffle.api.frame.FrameUtil;
 import com.oracle.truffle.api.frame.VirtualFrame;
+import com.oracle.truffle.api.nodes.DirectCallNode;
+import com.oracle.truffle.api.nodes.ExplodeLoop;
 import com.oracle.truffle.api.nodes.NodeInfo;
 import com.oracle.truffle.api.profiles.ConditionProfile;
+import org.enso.compiler.Compiler;
 import org.enso.interpreter.node.ExpressionNode;
 import org.enso.interpreter.node.callable.ExecuteCallNode;
 import org.enso.interpreter.node.callable.ExecuteCallNodeGen;
@@ -13,19 +18,19 @@ import org.enso.interpreter.node.callable.function.CreateFunctionNode;
 import org.enso.interpreter.runtime.callable.atom.Atom;
 import org.enso.interpreter.runtime.callable.atom.AtomConstructor;
 import org.enso.interpreter.runtime.callable.function.Function;
+import org.enso.interpreter.runtime.state.Stateful;
 import org.enso.interpreter.runtime.type.TypesGen;
 
 /** An implementation of the case expression specialised to working on constructors. */
 @NodeInfo(shortName = "ConstructorMatch")
 public abstract class ConstructorBranchNode extends BranchNode {
   private final AtomConstructor matcher;
-  private @Child ExpressionNode branch;
-  private @Child ExecuteCallNode executeCallNode = ExecuteCallNodeGen.create();
+  private @Child DirectCallNode callNode;
   private final ConditionProfile profile = ConditionProfile.createCountingProfile();
 
-  ConstructorBranchNode(AtomConstructor matcher, CreateFunctionNode branch) {
+  ConstructorBranchNode(AtomConstructor matcher, RootCallTarget branch) {
     this.matcher = matcher;
-    this.branch = branch;
+    this.callNode = DirectCallNode.create(branch);
   }
 
   /**
@@ -35,7 +40,7 @@ public abstract class ConstructorBranchNode extends BranchNode {
    * @param branch the expression to be executed if (@code matcher} matches
    * @return a node for matching in a case expression
    */
-  public static ConstructorBranchNode build(AtomConstructor matcher, CreateFunctionNode branch) {
+  public static ConstructorBranchNode build(AtomConstructor matcher, RootCallTarget branch) {
     return ConstructorBranchNodeGen.create(matcher, branch);
   }
 
@@ -46,17 +51,19 @@ public abstract class ConstructorBranchNode extends BranchNode {
    * all the atom's fields as arguments.
    *
    * @param frame the stack frame in which to execute
+   * @param state current monadic state
    * @param target the atom to destructure
    */
   @Specialization
-  public void doAtom(VirtualFrame frame, Atom target) {
-    Object state = FrameUtil.getObjectSafe(frame, getStateFrameSlot());
+  public void doAtom(VirtualFrame frame, Object state, Atom target) {
     if (profile.profile(matcher == target.getConstructor())) {
-      Function function = TypesGen.asFunction(branch.executeGeneric(frame));
-
       // Note [Caller Info For Case Branches]
-      throw new BranchSelectedException(
-          executeCallNode.executeCall(function, null, state, target.getFields()));
+      Stateful result =
+          (Stateful)
+              callNode.call(
+                  Function.ArgumentsHelper.buildArguments(
+                      frame.materialize(), state, target.getFields()));
+      throw new BranchSelectedException(result);
     }
   }
 
@@ -67,7 +74,7 @@ public abstract class ConstructorBranchNode extends BranchNode {
    * @param target the object to execute on
    */
   @Fallback
-  public void doFallback(VirtualFrame frame, Object target) {}
+  public void doFallback(VirtualFrame frame, Object state, Object target) {}
 
   /* Note [Caller Info For Case Branches]
    * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

engine/runtime/src/main/java/org/enso/interpreter/node/expression/builtin/InstantiateAtomNode.java

@@ -1,19 +1,17 @@
 package org.enso.interpreter.node.expression.builtin;
 
 import com.oracle.truffle.api.frame.VirtualFrame;
-import com.oracle.truffle.api.nodes.Node;
 import com.oracle.truffle.api.nodes.NodeInfo;
 import com.oracle.truffle.api.nodes.RootNode;
 import org.enso.interpreter.Language;
 import org.enso.interpreter.node.ExpressionNode;
-import org.enso.interpreter.runtime.callable.atom.AtomConstructor;
 import org.enso.interpreter.runtime.callable.function.Function;
 import org.enso.interpreter.runtime.state.Stateful;
 
 /** This node represents the process of instantiating an atom at runtime. */
 @NodeInfo(shortName = "constructor::", description = "An atom instantiation at runtime.")
 public class InstantiateAtomNode extends RootNode {
-  private @Node.Child ExpressionNode instantiator;
+  private @Child ExpressionNode instantiator;
   private final String name;
 
   private InstantiateAtomNode(Language language, String name, ExpressionNode instantiator) {
@@ -22,7 +20,8 @@ public class InstantiateAtomNode extends RootNode {
     this.instantiator = instantiator;
   }
 
-  /** Executes this node.
+  /**
+   * Executes this node.
    *
    * @param frame the language frame being executed
    * @return the result of executing this node
@@ -34,7 +33,8 @@ public class InstantiateAtomNode extends RootNode {
         instantiator.executeGeneric(frame));
   }
 
-  /** Returns a string representation of this node.
+  /**
+   * Returns a string representation of this node.
    *
    * @return a string representation of this node
    */
@@ -43,7 +43,8 @@ public class InstantiateAtomNode extends RootNode {
     return "constructor::" + name;
   }
 
-  /** Creates an instance of this node.
+  /**
+   * Creates an instance of this node.
    *
    * @param language the language for which the node is created
    * @param name the name of the atom being instantated

engine/runtime/src/main/java/org/enso/interpreter/node/expression/builtin/bool/IfThenElseNode.java

@@ -4,6 +4,7 @@ import com.oracle.truffle.api.nodes.Node;
 import com.oracle.truffle.api.profiles.ConditionProfile;
 import org.enso.interpreter.dsl.BuiltinMethod;
 import org.enso.interpreter.dsl.MonadicState;
+import org.enso.interpreter.dsl.Suspend;
 import org.enso.interpreter.node.BaseNode;
 import org.enso.interpreter.node.callable.thunk.ThunkExecutorNode;
 import org.enso.interpreter.runtime.callable.argument.Thunk;
@@ -18,7 +19,11 @@ public class IfThenElseNode extends Node {
   private @Child ThunkExecutorNode rightThunkExecutorNode = ThunkExecutorNode.build();
   private final ConditionProfile condProfile = ConditionProfile.createCountingProfile();
 
-  Stateful execute(@MonadicState Object state, boolean _this, Thunk if_true, Thunk if_false) {
+  Stateful execute(
+      @MonadicState Object state,
+      boolean _this,
+      @Suspend Object if_true,
+      @Suspend Object if_false) {
     if (condProfile.profile(_this)) {
       return leftThunkExecutorNode.executeThunk(if_true, state, BaseNode.TailStatus.TAIL_DIRECT);
     } else {

engine/runtime/src/main/java/org/enso/interpreter/node/expression/builtin/bool/IfThenNode.java

@@ -7,6 +7,7 @@ import com.oracle.truffle.api.profiles.ConditionProfile;
 import org.enso.interpreter.Language;
 import org.enso.interpreter.dsl.BuiltinMethod;
 import org.enso.interpreter.dsl.MonadicState;
+import org.enso.interpreter.dsl.Suspend;
 import org.enso.interpreter.node.BaseNode;
 import org.enso.interpreter.node.callable.thunk.ThunkExecutorNode;
 import org.enso.interpreter.runtime.Context;
@@ -25,11 +26,11 @@ public abstract class IfThenNode extends Node {
     return IfThenNodeGen.create();
   }
 
-  abstract Stateful execute(@MonadicState Object state, boolean _this, Thunk if_true);
+  abstract Stateful execute(@MonadicState Object state, boolean _this, @Suspend Object if_true);
 
   @Specialization
   Stateful doExecute(
-      Object state, boolean _this, Thunk if_true, @CachedContext(Language.class) Context context) {
+      Object state, boolean _this, Object if_true, @CachedContext(Language.class) Context context) {
     if (condProfile.profile(_this)) {
       return leftThunkExecutorNode.executeThunk(if_true, state, BaseNode.TailStatus.TAIL_DIRECT);
     } else {

engine/runtime/src/main/java/org/enso/interpreter/node/expression/builtin/error/CatchPanicNode.java

@@ -7,6 +7,7 @@ import com.oracle.truffle.api.nodes.Node;
 import org.enso.interpreter.Language;
 import org.enso.interpreter.dsl.BuiltinMethod;
 import org.enso.interpreter.dsl.MonadicState;
+import org.enso.interpreter.dsl.Suspend;
 import org.enso.interpreter.node.BaseNode;
 import org.enso.interpreter.node.callable.thunk.ThunkExecutorNode;
 import org.enso.interpreter.runtime.Context;
@@ -26,13 +27,13 @@ public abstract class CatchPanicNode extends Node {
     return CatchPanicNodeGen.create();
   }
 
-  abstract Stateful execute(@MonadicState Object state, Object _this, Thunk action);
+  abstract Stateful execute(@MonadicState Object state, Object _this, @Suspend Object action);
 
   @Specialization
   Stateful doExecute(
       @MonadicState Object state,
       Object _this,
-      Thunk action,
+      Object action,
       @CachedContext(Language.class) Context ctx) {
     try {
       return thunkExecutorNode.executeThunk(action, state, BaseNode.TailStatus.NOT_TAIL);

engine/runtime/src/main/java/org/enso/interpreter/node/expression/builtin/function/ApplicationOperator.java

@@ -4,6 +4,7 @@ import com.oracle.truffle.api.frame.VirtualFrame;
 import com.oracle.truffle.api.nodes.Node;
 import org.enso.interpreter.dsl.BuiltinMethod;
 import org.enso.interpreter.dsl.MonadicState;
+import org.enso.interpreter.dsl.Suspend;
 import org.enso.interpreter.node.BaseNode;
 import org.enso.interpreter.node.callable.InvokeCallableNode;
 import org.enso.interpreter.runtime.callable.argument.CallArgumentInfo;
@@ -27,7 +28,8 @@ public class ApplicationOperator extends Node {
     invokeCallableNode.setTailStatus(BaseNode.TailStatus.TAIL_DIRECT);
   }
 
-  Stateful execute(VirtualFrame frame, @MonadicState Object state, Function _this, Thunk argument) {
+  Stateful execute(
+      VirtualFrame frame, @MonadicState Object state, Function _this, @Suspend Object argument) {
     return invokeCallableNode.execute(_this, frame, state, new Object[] {argument});
   }
 }

engine/runtime/src/main/java/org/enso/interpreter/node/expression/builtin/interop/generic/EvalNode.java

@@ -0,0 +1,70 @@
+package org.enso.interpreter.node.expression.builtin.interop.generic;
+
+import com.oracle.truffle.api.CallTarget;
+import com.oracle.truffle.api.dsl.Cached;
+import com.oracle.truffle.api.dsl.CachedContext;
+import com.oracle.truffle.api.dsl.ReportPolymorphism;
+import com.oracle.truffle.api.dsl.Specialization;
+import com.oracle.truffle.api.nodes.DirectCallNode;
+import com.oracle.truffle.api.nodes.IndirectCallNode;
+import com.oracle.truffle.api.nodes.Node;
+import com.oracle.truffle.api.source.Source;
+import org.enso.interpreter.Language;
+import org.enso.interpreter.dsl.BuiltinMethod;
+import org.enso.interpreter.node.expression.builtin.interop.syntax.HostValueToEnsoNode;
+import org.enso.interpreter.node.expression.builtin.text.util.ToJavaStringNode;
+import org.enso.interpreter.runtime.Context;
+import org.enso.interpreter.runtime.data.text.Text;
+
+@BuiltinMethod(
+    type = "Polyglot",
+    name = "eval",
+    description = "Evaluates a foreign language string.")
+@ReportPolymorphism
+public abstract class EvalNode extends Node {
+  static final int LIMIT = 10;
+
+  static EvalNode build() {
+    return EvalNodeGen.create();
+  }
+
+  abstract Object execute(Object _this, Text language, Text code);
+
+  @Specialization(
+      guards = {"cachedLanguage == language", "cachedCode == code"},
+      limit = "LIMIT")
+  Object doCached(
+      Object _this,
+      Text language,
+      Text code,
+      @CachedContext(Language.class) Context context,
+      @Cached("language") Text cachedLanguage,
+      @Cached("code") Text cachedCode,
+      @Cached("build()") ToJavaStringNode toJavaStringNode,
+      @Cached("parse(context, cachedLanguage, cachedCode, toJavaStringNode)") CallTarget callTarget,
+      @Cached("create(callTarget)") DirectCallNode callNode,
+      @Cached("build()") HostValueToEnsoNode hostValueToEnsoNode) {
+    return hostValueToEnsoNode.execute(callNode.call());
+  }
+
+  @Specialization(replaces = "doCached")
+  Object doUncached(
+      Object _this,
+      Text language,
+      Text code,
+      @CachedContext(Language.class) Context context,
+      @Cached IndirectCallNode callNode,
+      @Cached("build()") ToJavaStringNode toJavaStringNode,
+      @Cached("build()") HostValueToEnsoNode hostValueToEnsoNode) {
+    CallTarget ct = parse(context, language, code, toJavaStringNode);
+    return hostValueToEnsoNode.execute(callNode.call(ct));
+  }
+
+  CallTarget parse(Context context, Text language, Text code, ToJavaStringNode toJavaStringNode) {
+    String languageStr = toJavaStringNode.execute(language);
+    String codeStr = toJavaStringNode.execute(code);
+
+    Source source = Source.newBuilder(languageStr, codeStr, "<polyglot_eval>").build();
+    return context.getEnvironment().parsePublic(source);
+  }
+}

engine/runtime/src/main/java/org/enso/interpreter/node/expression/builtin/interop/generic/ExecuteNode.java

@@ -8,6 +8,7 @@ import com.oracle.truffle.api.nodes.Node;
 import com.oracle.truffle.api.profiles.BranchProfile;
 import org.enso.interpreter.Constants;
 import org.enso.interpreter.dsl.BuiltinMethod;
+import org.enso.interpreter.node.expression.builtin.interop.syntax.HostValueToEnsoNode;
 import org.enso.interpreter.runtime.data.Array;
 import org.enso.interpreter.runtime.error.PanicException;
 
@@ -18,11 +19,12 @@ import org.enso.interpreter.runtime.error.PanicException;
 public class ExecuteNode extends Node {
   private @Child InteropLibrary library =
       InteropLibrary.getFactory().createDispatched(Constants.CacheSizes.BUILTIN_INTEROP_DISPATCH);
+  private @Child HostValueToEnsoNode hostValueToEnsoNode = HostValueToEnsoNode.build();
   private final BranchProfile err = BranchProfile.create();
 
   Object execute(Object _this, Object callable, Array arguments) {
     try {
-      return library.execute(callable, arguments.getItems());
+      return hostValueToEnsoNode.execute(library.execute(callable, arguments.getItems()));
     } catch (UnsupportedMessageException | ArityException | UnsupportedTypeException e) {
       err.enter();
       throw new PanicException(e.getMessage(), this);

engine/runtime/src/main/java/org/enso/interpreter/node/expression/builtin/resource/BracketNode.java

@@ -5,6 +5,7 @@ import com.oracle.truffle.api.frame.VirtualFrame;
 import com.oracle.truffle.api.nodes.Node;
 import org.enso.interpreter.dsl.BuiltinMethod;
 import org.enso.interpreter.dsl.MonadicState;
+import org.enso.interpreter.dsl.Suspend;
 import org.enso.interpreter.node.BaseNode;
 import org.enso.interpreter.node.callable.InvokeCallableNode;
 import org.enso.interpreter.node.callable.thunk.ThunkExecutorNode;
@@ -50,7 +51,7 @@ public abstract class BracketNode extends Node {
       @MonadicState Object state,
       VirtualFrame frame,
       Object _this,
-      Thunk constructor,
+      @Suspend Object constructor,
       Object destructor,
       Object action);
 
@@ -59,7 +60,7 @@ public abstract class BracketNode extends Node {
       Object state,
       VirtualFrame frame,
       Object _this,
-      Thunk constructor,
+      Object constructor,
       Object destructor,
       Object action) {
     Stateful resourceStateful =

engine/runtime/src/main/java/org/enso/interpreter/node/expression/builtin/runtime/NoInlineNode.java

@@ -4,6 +4,7 @@ import com.oracle.truffle.api.CompilerDirectives;
 import com.oracle.truffle.api.nodes.Node;
 import org.enso.interpreter.dsl.BuiltinMethod;
 import org.enso.interpreter.dsl.MonadicState;
+import org.enso.interpreter.dsl.Suspend;
 import org.enso.interpreter.node.BaseNode;
 import org.enso.interpreter.node.callable.thunk.ThunkExecutorNode;
 import org.enso.interpreter.runtime.callable.argument.Thunk;
@@ -17,7 +18,7 @@ public class NoInlineNode extends Node {
   private @Child ThunkExecutorNode thunkExecutorNode = ThunkExecutorNode.build();
 
   @CompilerDirectives.TruffleBoundary
-  Stateful execute(@MonadicState Object state, Object _this, Thunk action) {
+  Stateful execute(@MonadicState Object state, Object _this, @Suspend Object action) {
     return thunkExecutorNode.executeThunk(action, state, BaseNode.TailStatus.NOT_TAIL);
   }
 }

engine/runtime/src/main/java/org/enso/interpreter/node/expression/builtin/state/RunStateNode.java

@@ -7,6 +7,7 @@ import com.oracle.truffle.api.dsl.Specialization;
 import com.oracle.truffle.api.nodes.Node;
 import org.enso.interpreter.dsl.BuiltinMethod;
 import org.enso.interpreter.dsl.MonadicState;
+import org.enso.interpreter.dsl.Suspend;
 import org.enso.interpreter.node.BaseNode;
 import org.enso.interpreter.node.callable.thunk.ThunkExecutorNode;
 import org.enso.interpreter.runtime.callable.argument.Thunk;
@@ -29,11 +30,15 @@ public abstract class RunStateNode extends Node {
   private @Child ThunkExecutorNode thunkExecutorNode = ThunkExecutorNode.build();
 
   abstract Stateful execute(
-      @MonadicState Object state, Object _this, Object key, Object local_state, Thunk computation);
+      @MonadicState Object state,
+      Object _this,
+      Object key,
+      Object local_state,
+      @Suspend Object computation);
 
   @Specialization
   Stateful doEmpty(
-      EmptyMap state, Object _this, Object key, Object local_state, Thunk computation) {
+      EmptyMap state, Object _this, Object key, Object local_state, Object computation) {
     SingletonMap localStateMap = new SingletonMap(key, local_state);
     Object result =
         thunkExecutorNode
@@ -44,7 +49,7 @@ public abstract class RunStateNode extends Node {
 
   @Specialization(guards = {"state.getKey() == key"})
   Stateful doSingletonSameKey(
-      SingletonMap state, Object _this, Object key, Object local_state, Thunk computation) {
+      SingletonMap state, Object _this, Object key, Object local_state, Object computation) {
     SingletonMap localStateContainer = new SingletonMap(state.getKey(), local_state);
     Stateful res =
         thunkExecutorNode.executeThunk(
@@ -63,7 +68,7 @@ public abstract class RunStateNode extends Node {
       Object _this,
       Object key,
       Object local_state,
-      Thunk computation,
+      Object computation,
       @Cached("key") Object cachedNewKey,
       @Cached("state.getKey()") Object cachedOldKey,
       @Cached(value = "buildSmallKeys(cachedNewKey, cachedOldKey)", dimensions = 1)
@@ -77,7 +82,7 @@ public abstract class RunStateNode extends Node {
 
   @Specialization
   Stateful doSingletonNewKeyUncached(
-      SingletonMap state, Object _this, Object key, Object local_state, Thunk computation) {
+      SingletonMap state, Object _this, Object key, Object local_state, Object computation) {
     return doSingletonNewKeyCached(
         state,
         _this,
@@ -100,7 +105,7 @@ public abstract class RunStateNode extends Node {
       Object _this,
       Object key,
       Object local_state,
-      Thunk computation,
+      Object computation,
       @Cached("key") Object cachedNewKey,
       @Cached(value = "state.getKeys()", dimensions = 1) Object[] cachedOldKeys,
       @Cached("state.indexOf(key)") int index,
@@ -125,7 +130,7 @@ public abstract class RunStateNode extends Node {
       Object _this,
       Object key,
       Object local_state,
-      Thunk computation,
+      Object computation,
       @Cached("key") Object cachedNewKey,
       @Cached(value = "state.getKeys()", dimensions = 1) Object[] cachedOldKeys,
       @Cached("state.indexOf(key)") int index) {
@@ -144,7 +149,7 @@ public abstract class RunStateNode extends Node {
 
   @Specialization
   Stateful doMultiUncached(
-      SmallMap state, Object _this, Object key, Object local_state, Thunk computation) {
+      SmallMap state, Object _this, Object key, Object local_state, Object computation) {
     int idx = state.indexOf(key);
     if (idx == SmallMap.NOT_FOUND) {
       return doMultiNewKeyCached(

engine/runtime/src/main/java/org/enso/interpreter/node/expression/builtin/thread/WithInterruptHandlerNode.java

@@ -3,6 +3,7 @@ package org.enso.interpreter.node.expression.builtin.thread;
 import com.oracle.truffle.api.nodes.Node;
 import org.enso.interpreter.dsl.BuiltinMethod;
 import org.enso.interpreter.dsl.MonadicState;
+import org.enso.interpreter.dsl.Suspend;
 import org.enso.interpreter.node.BaseNode;
 import org.enso.interpreter.node.callable.thunk.ThunkExecutorNode;
 import org.enso.interpreter.runtime.callable.argument.Thunk;
@@ -18,7 +19,7 @@ public class WithInterruptHandlerNode extends Node {
   private @Child ThunkExecutorNode handlerExecutorNode = ThunkExecutorNode.build();
 
   Stateful execute(
-      @MonadicState Object state, Object _this, Thunk action, Thunk interrupt_handler) {
+      @MonadicState Object state, Object _this, @Suspend Object action, @Suspend Object interrupt_handler) {
     try {
       return actExecutorNode.executeThunk(action, state, BaseNode.TailStatus.NOT_TAIL);
     } catch (ThreadInterruptedException e) {

engine/runtime/src/main/java/org/enso/interpreter/runtime/builtin/Polyglot.java

@@ -65,6 +65,7 @@ public class Polyglot {
     scope.registerMethod(polyglot, "execute", ExecuteMethodGen.makeFunction(language));
     scope.registerMethod(polyglot, "invoke", InvokeMethodGen.makeFunction(language));
     scope.registerMethod(polyglot, "new", InstantiateMethodGen.makeFunction(language));
+    scope.registerMethod(polyglot, "eval", EvalMethodGen.makeFunction(language));
     scope.registerMethod(polyglot, "get_member", GetMemberMethodGen.makeFunction(language));
     scope.registerMethod(polyglot, "get_members", GetMembersMethodGen.makeFunction(language));
   }

engine/runtime/src/main/java/org/enso/interpreter/runtime/callable/function/Function.java

@@ -8,6 +8,7 @@ import com.oracle.truffle.api.dsl.Cached;
 import com.oracle.truffle.api.dsl.CachedContext;
 import com.oracle.truffle.api.dsl.Specialization;
 import com.oracle.truffle.api.frame.MaterializedFrame;
+import com.oracle.truffle.api.frame.VirtualFrame;
 import com.oracle.truffle.api.interop.ArityException;
 import com.oracle.truffle.api.interop.InteropLibrary;
 import com.oracle.truffle.api.interop.TruffleObject;
@@ -83,8 +84,7 @@ public final class Function implements TruffleObject {
    * @param args argument definitons
    * @return a Function object with specified behavior and arguments
    */
-  public static Function fromBuiltinRootNode(
-      BuiltinRootNode node, ArgumentDefinition... args) {
+  public static Function fromBuiltinRootNode(BuiltinRootNode node, ArgumentDefinition... args) {
     RootCallTarget callTarget = Truffle.getRuntime().createCallTarget(node);
     FunctionSchema schema = new FunctionSchema(args);
     return new Function(callTarget, null, schema);
@@ -103,8 +103,7 @@ public final class Function implements TruffleObject {
   public static Function fromBuiltinRootNodeWithCallerFrameAccess(
       BuiltinRootNode node, ArgumentDefinition... args) {
     RootCallTarget callTarget = Truffle.getRuntime().createCallTarget(node);
-    FunctionSchema schema =
-        new FunctionSchema(FunctionSchema.CallerFrameAccess.FULL, args);
+    FunctionSchema schema = new FunctionSchema(FunctionSchema.CallerFrameAccess.FULL, args);
     return new Function(callTarget, null, schema);
   }
 
@@ -288,6 +287,19 @@ public final class Function implements TruffleObject {
       return new Object[] {function.getScope(), callerInfo, state, positionalArguments};
     }
 
+    /**
+     * Generates an array of arguments using the schema to be passed to a call target.
+     *
+     * @param frame the frame becoming the lexical scope
+     * @param state the state to execute the thunk with
+     * @param positionalArguments the positional arguments to the call target
+     * @return an array containing the necessary information to call an Enso function
+     */
+    public static Object[] buildArguments(
+        MaterializedFrame frame, Object state, Object[] positionalArguments) {
+      return new Object[] {frame, null, state, positionalArguments};
+    }
+
     /**
      * Generates an array of arguments using the schema to be passed to a call target.
      *

engine/runtime/src/main/scala/org/enso/compiler/codegen/IrToTruffle.scala

@@ -596,7 +596,10 @@ class IrToTruffle(
               .toArray[BranchNode]
 
             // Note [Pattern Match Fallbacks]
-            val matchExpr = CaseNode.build(scrutineeNode, cases)
+            val matchExpr = CaseNode.build(
+              scrutineeNode,
+              cases
+            )
             setLocation(matchExpr, location)
           } else {
             val invalidBranches = maybeCases.collect {
@@ -644,7 +647,8 @@ class IrToTruffle(
             branch.location
           )
 
-          val branchNode = CatchAllBranchNode.build(branchCodeNode)
+          val branchNode =
+            CatchAllBranchNode.build(branchCodeNode.getCallTarget)
 
           Right(branchNode)
         case cons @ Pattern.Constructor(constructor, _, _, _, _) =>
@@ -704,11 +708,14 @@ class IrToTruffle(
             val bool = context.getBuiltins.bool()
             val branchNode: BranchNode =
               if (atomCons == bool.getTrue) {
-                BooleanBranchNode.build(true, branchCodeNode)
+                BooleanBranchNode.build(true, branchCodeNode.getCallTarget)
               } else if (atomCons == bool.getFalse) {
-                BooleanBranchNode.build(false, branchCodeNode)
+                BooleanBranchNode.build(false, branchCodeNode.getCallTarget)
               } else {
-                ConstructorBranchNode.build(atomCons, branchCodeNode)
+                ConstructorBranchNode.build(
+                  atomCons,
+                  branchCodeNode.getCallTarget
+                )
               }
 
             branchNode
@@ -1170,11 +1177,17 @@ class IrToTruffle(
             )
             .unsafeAs[AliasAnalysis.Info.Scope.Child]
 
-          val shouldSuspend = shouldBeSuspended.getOrElse(
-            throw new CompilerError(
-              "Demand analysis information missing from call argument."
-            )
-          )
+          val shouldSuspend = value match {
+            case _: IR.Name => false
+            case _: IR.Literal.Text => false
+            case _: IR.Literal.Number => false
+            case _ =>
+              shouldBeSuspended.getOrElse(
+                throw new CompilerError(
+                  "Demand analysis information missing from call argument."
+                )
+              )
+          }
 
           val childScope = if (shouldSuspend) {
             scope.createChild(scopeInfo.scope)

engine/runtime/src/test/scala/org/enso/interpreter/test/semantic/CodeLocationsTest.scala

@@ -279,7 +279,6 @@ class CodeLocationsTest extends InterpreterTest {
         instrumenter.assertNodeExists(55, 67, classOf[CaseNode])
         instrumenter.assertNodeExists(60, 1, classOf[ReadLocalVariableNode])
         instrumenter.assertNodeExists(103, 3, classOf[IntegerLiteralNode])
-        instrumenter.assertNodeExists(73, 33, classOf[CreateFunctionNode])
 
         eval(code) shouldEqual 100
     }

lib/scala/interpreter-dsl/src/main/java/org/enso/interpreter/dsl/Suspend.java

@@ -0,0 +1,11 @@
+package org.enso.interpreter.dsl;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/** An interface marking an argument as suspended. */
+@Target(ElementType.PARAMETER)
+@Retention(RetentionPolicy.SOURCE)
+public @interface Suspend {}

lib/scala/interpreter-dsl/src/main/java/org/enso/interpreter/dsl/model/MethodDefinition.java

@@ -2,6 +2,7 @@ package org.enso.interpreter.dsl.model;
 
 import org.enso.interpreter.dsl.BuiltinMethod;
 import org.enso.interpreter.dsl.MonadicState;
+import org.enso.interpreter.dsl.Suspend;
 
 import javax.annotation.processing.ProcessingEnvironment;
 import javax.lang.model.element.*;
@@ -119,7 +120,10 @@ public class MethodDefinition {
               "The execute method does not take `this` argument. At least one positional argument must be named `_this`.",
               element);
     }
-    return definesThis;
+
+    boolean argsValid = arguments.stream().allMatch(arg -> arg.validate(processingEnvironment));
+
+    return definesThis && argsValid;
   }
 
   /** @return the package name this method was declared in. */
@@ -188,7 +192,9 @@ public class MethodDefinition {
     private final boolean isState;
     private final boolean isFrame;
     private final boolean isCallerInfo;
+    private final boolean isSuspended;
     private final int position;
+    private final VariableElement element;
 
     /**
      * Creates a new instance of this class.
@@ -197,17 +203,32 @@ public class MethodDefinition {
      * @param position the position (0-indexed) of this argument in the arguments list.
      */
     public ArgumentDefinition(VariableElement element, int position) {
+      this.element = element;
       type = element.asType();
       String[] typeNameSegments = type.toString().split("\\.");
       typeName = typeNameSegments[typeNameSegments.length - 1];
       String originalName = element.getSimpleName().toString();
       name = originalName.equals("_this") ? "this" : originalName;
       isState = element.getAnnotation(MonadicState.class) != null && type.toString().equals(OBJECT);
+      isSuspended = element.getAnnotation(Suspend.class) != null;
       isFrame = type.toString().equals(VIRTUAL_FRAME);
       isCallerInfo = type.toString().equals(CALLER_INFO);
       this.position = position;
     }
 
+    public boolean validate(ProcessingEnvironment processingEnvironment) {
+      if (type.toString().equals(THUNK)) {
+        processingEnvironment
+            .getMessager()
+            .printMessage(
+                Diagnostic.Kind.ERROR,
+                "Argument must not be typed as Thunk. Use @Suspend Object instead.",
+                element);
+        return false;
+      }
+      return true;
+    }
+
     /** @return whether this argument should be passed the monadic state. */
     public boolean isState() {
       return isState;
@@ -265,7 +286,7 @@ public class MethodDefinition {
 
     /** @return whether this argument is expected to be passed suspended. */
     public boolean isSuspended() {
-      return type.toString().equals(THUNK);
+      return isSuspended;
     }
   }
 }

std-bits/src/main/java/org/enso/base/Text_Utils.java

@@ -95,4 +95,15 @@ public class Text_Utils {
   public static boolean starts_with(String str, String prefix) {
     return str.startsWith(prefix);
   }
+
+  /**
+   * Checks whether {@code a} is lexicographically before {@code b}.
+   *
+   * @param a the left operand
+   * @param b the right operand
+   * @return whether {@code a} is before {@code b}.
+   */
+  public static boolean lt(String a, String b) {
+    return a.compareTo(b) < 0;
+  }
 }

test/Benchmarks/src/Collections.enso

@@ -2,6 +2,8 @@ from Base import all
 import Builtins
 import Base.Bench_Utils
 
+polyglot java import java.util.Random
+
 gen_list len = 0.upto len . fold Nil (l -> i -> Cons i+1 l)
 
 sum_list_meta list =
@@ -14,6 +16,12 @@ sum_list_meta list =
     res = folder 0 list
     res
 
+sum_recur n = if n == 0 then 0 else 1 + here.sum_recur n-1
+
+build_map size =
+    rand = Random.new [].to_array
+    0.upto size . fold Map.empty (m -> i -> m.insert (rand.nextInt [10000]) i)
+
 main =
     mil = 1000000
     list = here.gen_list mil
@@ -23,3 +31,4 @@ main =
     Bench_Utils.measure (list.fold 0 (+)) "list fold" 1000 10
     Bench_Utils.measure (vec.fold 0 (+)) "vector fold" 1000 10
     Bench_Utils.measure (vec_decimal.fold 0 (+)) "vector decimal fold" 1000 10
+    Bench_Utils.measure (here.build_map 10000) "build a map" 100 10

test/Benchmarks/src/Main.enso

@@ -41,7 +41,8 @@ sum_co_state_body =
     acc = State.get Sum
     State.put Counter n-1
     State.put Sum     acc+n
-    if n == 0 then acc else @Tail_Call here.sum_co_state_body
+    if n == 0 then acc else
+        @Tail_Call here.sum_co_state_body
 
 sum_co_state n =
     res = State.run Counter n (State.run Sum 0 here.sum_co_state_body)
@@ -67,7 +68,6 @@ sum_co n =
 
 main =
     hundred_mil = 100000000
-    IO.println (here.sum_co 1000)
     IO.println "Measuring Sum TCO Corecursive"
     Bench_Utils.measure (here.sum_co hundred_mil) "sum_tco_corecursive" 100 10
     IO.println "Measuring Sum TCO Decimal"

test/Test/src/Data/Map_Spec.enso

@@ -0,0 +1,14 @@
+from Base import all
+
+import Base.Test
+
+spec = describe "Maps" <|
+    it "should allow inserting and looking up values" <|
+        m = Map.empty . insert "foo" 134 . insert "bar" 654 . insert "baz" "spam"
+        m.get "foo" . should equal 134
+        m.get "bar" . should equal 654
+        m.get "baz" . should equal "spam"
+        m.get "nope" . catch e->e . should_equal (Map.No_Value_For_Key "nope")
+    it "should convert the whole map to a vector" <|
+        m = Map.empty . insert 0 0 . insert 3 -5 . insert 1 2
+        m.to_vector.should equal [[0, 0], [1, 2], [3, -5]]

test/Test/src/Main.enso

@@ -8,6 +8,7 @@ import Test.Semantic.Names_Spec
 import Test.Semantic.Meta_Spec
 
 import Test.List_Spec
+import Test.Data.Map_Spec
 import Test.Number_Spec
 import Test.Process_Spec
 import Test.Vector.Spec as Vector_Spec
@@ -31,3 +32,4 @@ main = Test.Suite.runMain <|
     Time_Spec.spec
     File_Spec.spec
     Meta_Spec.spec
+    Map_Spec.spec

tools/performance/comparative-benchmark/benchmarks/haskell/package.yaml

@@ -16,6 +16,7 @@ library:
     - base
     - deepseq
     - containers
+    - random
 
 benchmarks:
   haskell-benchmark:

tools/performance/comparative-benchmark/benchmarks/haskell/src/Fixtures.hs

@@ -4,8 +4,10 @@ import Prelude
 
 import qualified Data.Map.Strict as Map
 
+import Control.Monad (foldM)
 import Data.Int (Int64)
 import Data.List (foldl')
+import System.Random (randomRIO)
 
 
 ------------------
@@ -69,4 +71,7 @@ myFoldl f z (Cons x xs) = let z' = z `f` x
                     in seq z' $ myFoldl f z' xs
 
 buildMap :: Integer -> Map.Map Integer Integer
-buildMap i = foldl' (\m i -> Map.insert i i m) Map.empty [0..i]
+buildMap n = foldl' (\m i -> Map.insert i i m) Map.empty [0..n]
+
+buildRandomMap :: Integer -> IO (Map.Map Integer Integer)
+buildRandomMap n = foldM (\m i -> fmap (\key -> Map.insert key i m) $ randomRIO (0, 10000)) Map.empty [0..n]

tools/performance/comparative-benchmark/benchmarks/haskell/test/bench/Main.hs

@@ -10,6 +10,7 @@ main :: IO ()
 main = defaultMain
     [
         bench "buildMap"        $ whnf Fixtures.buildMap Fixtures.tenThousand,
+        bench "buildMapRandom"  $ whnfIO $ Fixtures.buildRandomMap Fixtures.tenThousand,
         bench "sumTCO"          $ whnf Fixtures.sumTCO Fixtures.hundredMillion,
         bench "sumList"         $ whnf Fixtures.sumList Fixtures.millionElementList,
         bench "reverseList"     $ whnf Fixtures.reverseList Fixtures.millionElementList,