support underscores in function application, add sign entity

1 files changed, 12 insertions, 4 deletions

diff --git a/src/engine/entities/FunctionApplication.ts b/src/engine/entities/FunctionApplication.ts
index d907eca..175534c 100644
--- a/src/engine/entities/FunctionApplication.ts
+++ b/src/engine/entities/FunctionApplication.ts
@@ -34,6 +34,10 @@ import {
   interpret,
 } from "../../interpreter";
 
+const APPLICATION_RESULTS: Record<string, (gridPosition: Coord2D) => Entity> = {
+  _KEY: (gridPosition: Coord2D) => new Key(gridPosition),
+};
+
 export class FunctionApplication extends Entity {
   private static spriteSpec = SPRITE_SPECS.get(Sprites.BUBBLE) as SpriteSpec;
 
@@ -43,7 +47,9 @@ export class FunctionApplication extends Entity {
     super(EntityNames.FunctionApplication);
 
     this.symbolTable = new SymbolTable();
-    this.symbolTable.add("key");
+    Object.keys(APPLICATION_RESULTS).forEach((key) => {
+      this.symbolTable.add(key);
+    });
 
     const dimension = {
       width: FunctionApplication.spriteSpec.width,
@@ -109,9 +115,10 @@ export class FunctionApplication extends Entity {
       ComponentNames.LambdaTerm
     );
     const newCode = applicationTerm.code.replace("_INPUT", functionTerm.code);
+
     let result: DebrujinifiedLambdaTerm | null = null;
     try {
-      result = interpret(newCode, this.symbolTable);
+      result = interpret(newCode, this.symbolTable, true);
     } catch (e) {
       console.error(e);
       fail();
@@ -131,8 +138,9 @@ export class FunctionApplication extends Entity {
       applicationResultingEntity = new FunctionBox(grid.gridPosition, code);
     } else if ("name" in result) {
       const { name } = result;
-      if (name === "key") {
-        applicationResultingEntity = new Key(grid.gridPosition);
+      const entityFactory = APPLICATION_RESULTS[name];
+      if (entityFactory) {
+        game.addEntity(entityFactory(nextPosition));
       }
     } else {
       fail();