Core functions should return Oslo types, not JS types

src/compiler.js

@@ -25,6 +25,8 @@ module.exports = class Compiler {
       case AST.Number:
       case AST.String:
         return node.value
+      case AST.Boolean:
+        return node.value === true ? '#t' : '#f'
       case AST.Identifier:
         return this.compileNode(this.env.get(node.name))
       case AST.Conditional:
@@ -38,7 +40,7 @@ module.exports = class Compiler {
       case AST.Application:
         if (node.function.constructor === AST.Identifier) {
           let f = this.env.get(node.function.name)
-          return f(...node.args.map(arg => this.compileNode(arg)))
+          return this.compileNode(f(...node.args.map(arg => this.compileNode(arg))))
         } else if (node.function.constructor === AST.Lambda) {
           let env = new Env(this.env)
           node.function.parameters.forEach((param, index) => {

src/env.js

@@ -1,18 +1,20 @@
+const AST = require('../src/ast')
+
 module.exports = class Env {
   constructor(parent = null) {
     if (parent) {
       this.data = parent.data
     } else {
       this.data = {
-        '+': (a, b) => a + b,
-        '-': (a, b) => a - b,
-        '*': (a, b) => a * b,
-        '/': (a, b) => a / b,
-        '=': (a, b)  => a === b,
-        '>': (a, b)  => a > b,
-        '<': (a, b)  => a < b,
-        '>=': (a, b) => a >= b,
-        '<=': (a, b) => a <= b,
+        '+': (a, b) => new AST.Number({ value: a + b }),
+        '-': (a, b) => new AST.Number({ value: a - b }),
+        '*': (a, b) => new AST.Number({ value: a * b }),
+        '/': (a, b) => new AST.Number({ value: a / b }),
+        '=': (a, b) => new AST.Boolean({ value: a === b }),
+        '>': (a, b) => new AST.Boolean({ value: a > b }),
+        '<': (a, b) => new AST.Boolean({ value: a < b }),
+        '>=': (a, b) => new AST.Boolean({ value: a >= b }),
+        '<=': (a, b) => new AST.Boolean({ value: a <= b }),
       }
     }
   }

test/coreTest.js

@@ -5,17 +5,17 @@ test('comparison functions', t => {
   t.plan(5)
 
   let result = helpers.compile('(= 1 2)')
-  t.equal(result, 'false')
+  t.equal(result, '#f')
 
   result = helpers.compile('(> 5 4)')
-  t.equal(result, 'true')
+  t.equal(result, '#t')
 
   result = helpers.compile('(< 58 10)')
-  t.equal(result, 'false')
+  t.equal(result, '#f')
 
   result = helpers.compile('(>= 5 5)')
-  t.equal(result, 'true')
+  t.equal(result, '#t')
 
   result = helpers.compile('(<= 10 10)')
-  t.equal(result, 'true')
+  t.equal(result, '#t')
 })