diff --git a/src/Language/Go/Assignment.hs b/src/Language/Go/Assignment.hs
index a7e6cc44f..b7813b6e8 100644
--- a/src/Language/Go/Assignment.hs
+++ b/src/Language/Go/Assignment.hs
@@ -22,6 +22,7 @@ import qualified Data.Syntax.Literal as Literal
 import qualified Data.Syntax.Statement as Statement
 import qualified Data.Syntax.Type as Type
 import Data.Sum
+import GHC.Exts (fromList)
 import qualified Data.Term as Term
 import Prologue
 
@@ -91,6 +92,7 @@ type Syntax =
    , Syntax.Empty
    , Syntax.Identifier
    , Syntax.Program
+   , Syntax.Statements
    , Type.Annotation
    , Type.Array
    , Type.Function
@@ -111,7 +113,7 @@ assignment :: Assignment
 assignment = handleError program <|> parseError
 
 program :: Assignment
-program = makeTerm <$> symbol SourceFile <*> children (Syntax.Program <$> manyTerm expression)
+program = makeTerm <$> symbol SourceFile <*> children (Syntax.Program . fromList <$> manyTerm expression)
 
 expression :: Assignment
 expression = term (handleError (choice expressionChoices))
diff --git a/src/Language/Go/Syntax.hs b/src/Language/Go/Syntax.hs
index 9b47e4894..404dcb2e5 100644
--- a/src/Language/Go/Syntax.hs
+++ b/src/Language/Go/Syntax.hs
@@ -9,6 +9,7 @@ import           Data.Aeson
 import qualified Data.ByteString as B
 import qualified Data.ByteString.Char8 as BC
 import           Data.JSON.Fields
+import           Data.Syntax (Statements)
 import           Diffing.Algorithm
 import           Prologue
 import           System.FilePath.Posix
@@ -299,7 +300,7 @@ instance ToJSONFields1 Field
 instance Evaluatable Field
 
 
-data Package a = Package { packageName :: !a, packageContents :: ![a] }
+data Package a = Package { packageName :: !a, packageContents :: Statements a }
   deriving (Diffable, Eq, FreeVariables1, Declarations1, Foldable, Functor, Generic1, Hashable1, Mergeable, Ord, Show, Traversable)
 
 instance Eq1 Package where liftEq = genericLiftEq
diff --git a/src/Language/PHP/Assignment.hs b/src/Language/PHP/Assignment.hs
index 256f11948..7092fadfc 100644
--- a/src/Language/PHP/Assignment.hs
+++ b/src/Language/PHP/Assignment.hs
@@ -23,6 +23,7 @@ import qualified Data.Syntax.Statement as Statement
 import qualified Data.Syntax.Type as Type
 import qualified Data.Term as Term
 import qualified Language.PHP.Syntax as Syntax
+import GHC.Exts (fromList)
 import Prologue
 
 type Syntax = '[
@@ -140,7 +141,7 @@ bookend head list last = head : append last list
 
 -- | Assignment from AST in PHP's grammar onto a program in PHP's syntax.
 assignment :: Assignment
-assignment = handleError $ makeTerm <$> symbol Program <*> children (Syntax.Program <$> (bookend <$> (text <|> emptyTerm) <*> manyTerm statement <*> (text <|> emptyTerm))) <|> parseError
+assignment = handleError $ makeTerm <$> symbol Program <*> children (Syntax.Program . fromList <$> (bookend <$> (text <|> emptyTerm) <*> manyTerm statement <*> (text <|> emptyTerm))) <|> parseError
 
 term :: Assignment -> Assignment
 term term = contextualize (comment <|> textInterpolation) (postContextualize (comment <|> textInterpolation) term)
diff --git a/src/Language/Python/Assignment.hs b/src/Language/Python/Assignment.hs
index ddbcca6d8..b4b2514f8 100644
--- a/src/Language/Python/Assignment.hs
+++ b/src/Language/Python/Assignment.hs
@@ -25,6 +25,7 @@ import qualified Data.Syntax.Statement as Statement
 import qualified Data.Syntax.Type as Type
 import qualified Data.Term as Term
 import qualified Data.List.NonEmpty as NonEmpty
+import GHC.Exts (fromList)
 import Prologue
 
 
@@ -90,7 +91,7 @@ type Assignment = HasCallStack => Assignment.Assignment [] Grammar Term
 
 -- | Assignment from AST in Python's grammar onto a program in Python's syntax.
 assignment :: Assignment
-assignment = handleError $ makeTerm <$> symbol Module <*> children (Syntax.Program <$> manyTerm expression) <|> parseError
+assignment = handleError $ makeTerm <$> symbol Module <*> children (Syntax.Program . fromList <$> manyTerm expression) <|> parseError
 
 -- | Match a term optionally preceded by comment(s), or a sequence of comments if the term is not present.
 manyTerm :: Assignment -> Assignment.Assignment [] Grammar [Term]
diff --git a/src/Language/Ruby/Assignment.hs b/src/Language/Ruby/Assignment.hs
index be2683e5d..061dc2423 100644
--- a/src/Language/Ruby/Assignment.hs
+++ b/src/Language/Ruby/Assignment.hs
@@ -23,6 +23,7 @@ import qualified Data.Syntax.Literal as Literal
 import qualified Data.Syntax.Statement as Statement
 import qualified Data.Term as Term
 import qualified Language.Ruby.Syntax as Ruby.Syntax
+import GHC.Exts (fromList)
 import Prologue hiding (for)
 
 -- | The type of Ruby syntax.
@@ -77,6 +78,7 @@ type Syntax = '[
   , Syntax.Error
   , Syntax.Identifier
   , Syntax.Program
+  , Syntax.Statements
   , Ruby.Syntax.Class
   , Ruby.Syntax.Load
   , Ruby.Syntax.LowPrecedenceBoolean
@@ -92,7 +94,7 @@ type Assignment = Assignment' Term
 
 -- | Assignment from AST in Ruby’s grammar onto a program in Ruby’s syntax.
 assignment :: Assignment
-assignment = handleError $ makeTerm <$> symbol Program <*> children (Syntax.Program <$> many expression) <|> parseError
+assignment = handleError $ makeTerm <$> symbol Program <*> children (Syntax.Program . fromList <$> many expression) <|> parseError
 
 expression :: Assignment
 expression = term (handleError (choice expressionChoices))
@@ -230,7 +232,7 @@ singletonClass :: Assignment
 singletonClass = makeTerm <$> symbol SingletonClass <*> (withNewScope . children) (Ruby.Syntax.Class <$> expression <*> pure Nothing <*> expressions)
 
 module' :: Assignment
-module' = makeTerm <$> symbol Module <*> (withNewScope . children) (Ruby.Syntax.Module <$> expression <*> many expression)
+module' = makeTerm <$> symbol Module <*> (withNewScope . children) (Ruby.Syntax.Module <$> expression <*> manyStatements expression)
 
 scopeResolution :: Assignment
 scopeResolution = makeTerm <$> symbol ScopeResolution <*> children (Expression.ScopeResolution <$> many expression)
@@ -494,6 +496,9 @@ term term = contextualize comment term <|> makeTerm1 <$> (Syntax.Context <$> som
 manyTermsTill :: Assignment.Assignment [] Grammar Term -> Assignment.Assignment [] Grammar b -> Assignment.Assignment [] Grammar [Term]
 manyTermsTill step end = manyTill (step <|> comment) end
 
+manyStatements :: Assignment.Assignment [] Grammar Term -> Assignment.Assignment [] Grammar (Syntax.Statements Term)
+manyStatements expr = fromList <$> (many expr)
+
 -- | Match infix terms separated by any of a list of operators, assigning any comments following each operand.
 infixTerm :: HasCallStack
           => Assignment
diff --git a/src/Language/Ruby/Syntax.hs b/src/Language/Ruby/Syntax.hs
index 862d41eb7..8375f86e8 100644
--- a/src/Language/Ruby/Syntax.hs
+++ b/src/Language/Ruby/Syntax.hs
@@ -8,6 +8,7 @@ import           Data.Abstract.Path
 import qualified Data.ByteString.Char8 as BC
 import           Data.JSON.Fields
 import qualified Data.Language as Language
+import           Data.Syntax (Statements)
 import           Diffing.Algorithm
 import           Prelude hiding (fail)
 import           Prologue
@@ -146,7 +147,7 @@ instance Evaluatable Class where
     Rval <$> letrec' name (\addr ->
       subtermValue classBody <* makeNamespace name addr super)
 
-data Module a = Module { moduleIdentifier :: !a, moduleStatements :: ![a] }
+data Module a = Module { moduleIdentifier :: !a, moduleStatements :: Statements a }
   deriving (Diffable, Eq, Foldable, Functor, Generic1, Hashable1, Mergeable, Ord, Show, Traversable, FreeVariables1, Declarations1)
 
 instance Eq1 Module where liftEq = genericLiftEq
diff --git a/src/Language/TypeScript/Assignment.hs b/src/Language/TypeScript/Assignment.hs
index 5f2599129..914ba6380 100644
--- a/src/Language/TypeScript/Assignment.hs
+++ b/src/Language/TypeScript/Assignment.hs
@@ -22,6 +22,7 @@ import qualified Data.Syntax.Type as Type
 import qualified Data.Term as Term
 import Language.TypeScript.Grammar as Grammar
 import qualified Language.TypeScript.Syntax as TypeScript.Syntax
+import GHC.Exts (fromList)
 import Prologue
 
 -- | The type of TypeScript syntax.
@@ -89,6 +90,7 @@ type Syntax = '[
   , Syntax.Error
   , Syntax.Identifier
   , Syntax.Program
+  , Syntax.Statements
   , Syntax.Context
   , Type.Readonly
   , Type.TypeParameters
@@ -175,12 +177,15 @@ type Assignment = Assignment.Assignment [] Grammar Term
 
 -- | Assignment from AST in TypeScript’s grammar onto a program in TypeScript’s syntax.
 assignment :: Assignment
-assignment = handleError $ makeTerm <$> symbol Program <*> children (Syntax.Program <$> manyTerm statement) <|> parseError
+assignment = handleError $ makeTerm <$> symbol Program <*> children (Syntax.Program . fromList <$> manyTerm statement) <|> parseError
 
 -- | Match a term optionally preceded by comment(s), or a sequence of comments if the term is not present.
 manyTerm :: Assignment -> Assignment.Assignment [] Grammar [Term]
 manyTerm term = many (contextualize comment term <|> makeTerm1 <$> (Syntax.Context <$> some1 comment <*> emptyTerm))
 
+manyStatements :: Assignment.Assignment [] Grammar Term -> Assignment.Assignment [] Grammar (Syntax.Statements Term)
+manyStatements expr = fromList <$> (manyTerm expr)
+
 term :: Assignment -> Assignment
 term term = contextualize comment (postContextualize comment term)
 
@@ -763,11 +768,11 @@ internalModule :: Assignment
 internalModule = makeTerm <$> symbol Grammar.InternalModule <*> children (TypeScript.Syntax.InternalModule <$> term (string <|> identifier <|> nestedIdentifier) <*> statements)
 
 module' :: Assignment
-module' = makeTerm <$> symbol Module <*> children (TypeScript.Syntax.Module <$> term (string <|> identifier <|> nestedIdentifier) <*> (statements <|> pure []))
+module' = makeTerm <$> symbol Module <*> children (TypeScript.Syntax.Module <$> term (string <|> identifier <|> nestedIdentifier) <*> (statements <|> pure (fromList [])))
 
 
-statements :: Assignment.Assignment [] Grammar [Term]
-statements = symbol StatementBlock *> children (manyTerm statement)
+statements :: Assignment.Assignment [] Grammar (Syntax.Statements Term)
+statements = symbol StatementBlock *> children (manyStatements statement)
 
 arrowFunction :: Assignment
 arrowFunction = makeArrowFun <$> symbol ArrowFunction <*> children ((,,) <$> emptyTerm <*> (((\a b c -> (a, [b], c)) <$> emptyTerm <*> term identifier <*> emptyTerm) <|> callSignatureParts) <*> term (expression <|> statementBlock))
diff --git a/src/Language/TypeScript/Syntax.hs b/src/Language/TypeScript/Syntax.hs
index b05d22bd1..8be450a50 100644
--- a/src/Language/TypeScript/Syntax.hs
+++ b/src/Language/TypeScript/Syntax.hs
@@ -13,6 +13,7 @@ import           Data.JSON.Fields
 import qualified Data.Language as Language
 import qualified Data.Map as Map
 import           Data.Semigroup.Reducer (Reducer)
+import           Data.Syntax (Statements)
 import           Diffing.Algorithm
 import           Prelude
 import           Prologue
@@ -758,7 +759,7 @@ instance Ord1 Update where liftCompare = genericLiftCompare
 instance Show1 Update where liftShowsPrec = genericLiftShowsPrec
 instance Evaluatable Update
 
-data Module a = Module { moduleIdentifier :: !a, moduleStatements :: ![a] }
+data Module a = Module { moduleIdentifier :: !a, moduleStatements :: Statements a }
   deriving (Diffable, Eq, Foldable, Functor, Generic1, Hashable1, Mergeable, Ord, Show, Traversable, FreeVariables1, Declarations1)
 
 instance Eq1 Module where liftEq = genericLiftEq
@@ -775,7 +776,7 @@ instance Evaluatable Module where
 
 
 
-data InternalModule a = InternalModule { internalModuleIdentifier :: !a, internalModuleStatements :: ![a] }
+data InternalModule a = InternalModule { internalModuleIdentifier :: !a, internalModuleStatements :: Statements a }
   deriving (Diffable, Eq, Foldable, Functor, Generic1, Hashable1, Mergeable, Ord, Show, Traversable, FreeVariables1, Declarations1)
 
 instance Eq1 InternalModule where liftEq = genericLiftEq