Lambdas now work as expected

src/codegen/codegen.c

@@ -692,6 +692,8 @@ ResultType(GroundProgram, charptr) generateLambdaNode(SolsNode* node, SolsScope*
     char* lambdaId = malloc(sizeof(char) * 64);
     snprintf(lambdaId, 64, "__SOLS_LAMBDA_%zu", scope->tmpCounter++);
 
+    node->accessArg = groundCreateReference(VALREF, lambdaId);
+
     groundAddReferenceToInstruction(&signature, groundCreateReference(FNREF, lambdaId));
     ResultType(GroundArg, charptr) arg = createGroundArgFromSolsType(node->as.type.returnType);
     if (arg.error) {
@@ -712,8 +714,19 @@ ResultType(GroundProgram, charptr) generateLambdaNode(SolsNode* node, SolsScope*
 
     groundAddInstructionToProgram(&gp, signature);
 
+    // Create a scope for lambda arguments
+    // Lambdas do NOT have access to external state
+    SolsScope lambdaScope = {
+        .variables = NULL,
+        .tmpCounter = 0
+    };
+
+    for (size_t i = 0; i < node->as.type.children.count; i++) {
+        addVariableToScope(&lambdaScope, node->as.type.children.at[i].name, node->as.type.children.at[i].type);
+    }
+
     // Generate children and add then to this program
-    ResultType(GroundProgram, charptr) bodyCode = generateCode(&node->children.at[0], scope);
+    ResultType(GroundProgram, charptr) bodyCode = generateCode(&node->children.at[0], &lambdaScope);
     if (bodyCode.error) return bodyCode;
     for (size_t i = 0; i < bodyCode.as.success.size; i++) {
         groundAddInstructionToProgram(&gp, bodyCode.as.success.instructions[i]);