Create simple compiler class

Just numbers and strings for now

src/compiler.js

@@ -0,0 +1,23 @@
+const AST = require('./ast')
+
+module.exports = class Compiler {
+  constructor() {
+    this.result = ''
+  }
+
+  compile(tree) {
+    tree.forEach(node => {
+      this.result += this.compileNode(node)
+    })
+
+    return this.result
+  }
+
+  compileNode(node) {
+    switch (node.constructor) {
+      case AST.Number:
+      case AST.String:
+        return node.value
+    }
+  }
+}

src/index.js

@@ -1,11 +1,16 @@
+const Compiler = require('./compiler')
 const Lexer = require('./lexer')
 const Parser = require('./parser')
 
 module.exports = function oslo(source, context) {
   const lexer = new Lexer()
   const tokens = lexer.scan(source)
+
   const parser = new Parser(tokens)
   const tree = parser.parse()
 
-  return tree
+  const compiler = new Compiler()
+  const result = compiler.compile(tree)
+
+  return result
 }

test/compilerTest.js

@@ -0,0 +1,20 @@
+const test = require('tape')
+const helpers = require('./helpers')
+
+const AST = require('../src/ast')
+
+test('compiles numbers', t => {
+  t.plan(1)
+
+  const result = helpers.compile('5')
+
+  t.equal(result, "5")
+})
+
+test('compiles strings', t => {
+  t.plan(1)
+
+  const result = helpers.compile('"hello world"')
+
+  t.equal(result, "hello world")
+})

test/helpers.js

@@ -1,3 +1,4 @@
+const Compiler = require('../src/compiler')
 const Lexer = require('../src/lexer')
 const Parser = require('../src/parser')
 
@@ -11,7 +12,13 @@ const parse = source => {
   return parser.parse()
 }
 
+const compile = source => {
+  const compiler = new Compiler()
+  return compiler.compile(parse(source))
+}
+
 module.exports = {
-  scan: scan,
+  compile: compile,
   parse: parse,
+  scan: scan,
 }