4 files changed, 31 insertions, 13 deletions
diff --git a/src/eval-env/builtins.ts b/src/eval-env/builtins.ts
index 669a005..35f8485 100644
--- a/src/eval-env/builtins.ts
+++ b/src/eval-env/builtins.ts
@@ -6,10 +6,10 @@ const applyFunc = (ctx: Ctx, fn: Type | undefined, val: string): Type => {
   const resultType = (() => {
     const baseTypes = fn
       ?.getBaseTypes()
-      .flatMap((t) => t.getSymbol()?.getName())
+      .flatMap((t) => t.getSymbol()?.getName() ?? [])
 
-    if (baseTypes?.includes('Kind1')) {
-      const [_, resultNode] = ctx.createResult(
+    if (!!fn?.getProperty('return') || baseTypes?.includes('Kind1')) {
+      const [_key, resultNode] = ctx.createResult(
         `(${ctx.typeToString(fn)} & { input: ${val} })['return']`
       )
       return resultNode
@@ -53,7 +53,7 @@ const applyFunc = (ctx: Ctx, fn: Type | undefined, val: string): Type => {
   // TODO: Cleanup unwanted result node values
 
   if (!resultType) {
-    throw new Error('Fuck shit')
+    throw new Error('Couldnt get result for function application')
   }
 
   return resultType
diff --git a/src/eval-env/test.ts b/src/eval-env/test.ts
index 84ae138..4dd8c8d 100644
--- a/src/eval-env/test.ts
+++ b/src/eval-env/test.ts
@@ -2,7 +2,7 @@ import { Type } from 'ts-morph'
 import { Ctx } from '../types'
 
 export default (ctx: Ctx, args: Type[]) => ({
-  Test: async () => {
+  Test: ctx.withScope(async () => {
     const [msg, effs] = args
     process.stdout.write(` - ${ctx.getTypeValue(msg)} `)
 
@@ -13,12 +13,12 @@ export default (ctx: Ctx, args: Type[]) => ({
 
       console.log('[✓]')
     } catch (e) {
-      console.log('[TEST FAILED]')
+      // console.log('[TEST FAILED]')
       throw e
     }
 
     return []
-  },
+  }),
 
   Assert: async () => {
     if (!ctx.getTypeValue(args[0])) {
@@ -27,4 +27,15 @@ export default (ctx: Ctx, args: Type[]) => ({
 
     return []
   },
+
+  ShowAssertionError: async () => {
+    const [left, right] = args
+    console.log()
+    console.log(' | Assertion error:')
+    console.log(' |   - Left: ', ctx.typeToString(left))
+    console.log(' |   - Right:', ctx.typeToString(right))
+    console.log()
+
+    return []
+  },
 })
diff --git a/src/eval.ts b/src/eval.ts
index a7b1fb1..6eb72a1 100644
--- a/src/eval.ts
+++ b/src/eval.ts
@@ -32,6 +32,7 @@ export const evaluateType = async (
   const name = effTyp.getSymbol()?.getName()
   const args = effTyp.getTypeArguments()
 
+  // console.log('>>>>>', name)
   // console.log(ctx.typeToString(effTyp))
   // console.log(name, args.map(ctx.typeToString))
 
@@ -58,6 +59,7 @@ export const evaluateType = async (
     prevEnv = ctx.currentEnv
   }
 
+  // Evaluate custom effects (overrides builtins)
   if (name && ctx.hasCustomEffect(name)) {
     return ctx.runCustomEffect(name, args)
   }
diff --git a/src/index.ts b/src/index.ts
index f6d46d6..4775823 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -15,12 +15,17 @@ const main = () => {
     .description('Run a typescript .ts file')
     .argument('<file>', 'Typescript file to run')
     .action(async (filePath) => {
-      const ctx = createContext({ filePath })
-      const resultType = ctx.entryPoint.getType()
-      const effects = resultType.isTuple()
-        ? resultType.getTupleElements()
-        : [resultType]
-      await evalList(ctx, effects)
+      try {
+        const ctx = createContext({ filePath })
+        const resultType = ctx.entryPoint.getType()
+        const effects = resultType.isTuple()
+          ? resultType.getTupleElements()
+          : [resultType]
+        await evalList(ctx, effects)
+      } catch (e) {
+        console.error(e)
+        process.exit(1)
+      }
     })
 
   return program.parseAsync()