language: implement list indexing

ast/src/main/kotlin/gay/pizza/pork/ast/IndexedBy.kt

@@ -0,0 +1,29 @@
+// GENERATED CODE FROM PORK AST CODEGEN
+package gay.pizza.pork.ast
+
+import kotlinx.serialization.SerialName
+import kotlinx.serialization.Serializable
+
+@Serializable
+@SerialName("indexedBy")
+class IndexedBy(val expression: Expression, val index: Expression) : Expression() {
+  override val type: NodeType = NodeType.IndexedBy
+
+  override fun <T> visitChildren(visitor: NodeVisitor<T>): List<T> =
+    visitor.visitNodes(expression, index)
+
+  override fun <T> visit(visitor: NodeVisitor<T>): T =
+    visitor.visitIndexedBy(this)
+
+  override fun equals(other: Any?): Boolean {
+    if (other !is IndexedBy) return false
+    return other.expression == expression && other.index == index
+  }
+
+  override fun hashCode(): Int {
+    var result = expression.hashCode()
+    result = 31 * result + index.hashCode()
+    result = 31 * result + type.hashCode()
+    return result
+  }
+}

ast/src/main/kotlin/gay/pizza/pork/ast/NodeCoalescer.kt

@@ -35,6 +35,9 @@ class NodeCoalescer(val handler: (Node) -> Unit) : NodeVisitor<Unit> {
   override fun visitImportDeclaration(node: ImportDeclaration): Unit =
     handle(node)
 
+  override fun visitIndexedBy(node: IndexedBy): Unit =
+    handle(node)
+
   override fun visitInfixOperation(node: InfixOperation): Unit =
     handle(node)
 

ast/src/main/kotlin/gay/pizza/pork/ast/NodeParser.kt

@@ -30,6 +30,8 @@ interface NodeParser {
 
   fun parseImportDeclaration(): ImportDeclaration
 
+  fun parseIndexedBy(): IndexedBy
+
   fun parseInfixOperation(): InfixOperation
 
   fun parseIntegerLiteral(): IntegerLiteral

ast/src/main/kotlin/gay/pizza/pork/ast/NodeParserExtensions.kt

@@ -34,5 +34,6 @@ fun NodeParser.parse(type: NodeType): Node =
     NodeType.Continue -> parseContinue()
     NodeType.NoneLiteral -> parseNoneLiteral()
     NodeType.Native -> parseNative()
+    NodeType.IndexedBy -> parseIndexedBy()
     else -> throw RuntimeException("Unable to automatically parse type: ${type.name}")
   }

ast/src/main/kotlin/gay/pizza/pork/ast/NodeType.kt

@@ -17,6 +17,7 @@ enum class NodeType(val parent: NodeType? = null) {
   FunctionDefinition(Definition),
   If(Expression),
   ImportDeclaration(Declaration),
+  IndexedBy(Expression),
   InfixOperation(Expression),
   IntegerLiteral(Expression),
   LetAssignment(Expression),

ast/src/main/kotlin/gay/pizza/pork/ast/NodeVisitor.kt

@@ -24,6 +24,8 @@ interface NodeVisitor<T> {
 
   fun visitImportDeclaration(node: ImportDeclaration): T
 
+  fun visitIndexedBy(node: IndexedBy): T
+
   fun visitInfixOperation(node: InfixOperation): T
 
   fun visitIntegerLiteral(node: IntegerLiteral): T

ast/src/main/kotlin/gay/pizza/pork/ast/NodeVisitorExtensions.kt

@@ -31,6 +31,7 @@ fun <T> NodeVisitor<T>.visit(node: Node): T =
     is Continue -> visitContinue(node)
     is NoneLiteral -> visitNoneLiteral(node)
     is Native -> visitNative(node)
+    is IndexedBy -> visitIndexedBy(node)
   }
 
 fun <T> NodeVisitor<T>.visitNodes(vararg nodes: Node?): List<T> =