Added null type.

Author: mcollina

index.js

@@ -7,6 +7,7 @@ function build (schema) {
 
     ${$asString.toString()}
     ${$asNumber.toString()}
+    ${$asNull.toString()}
   `
   var main
 
@@ -22,6 +23,9 @@ function build (schema) {
     case 'number':
       main = $asNumber.name
       break
+    case 'null':
+      main = $asNull.name
+      break
     default:
       throw new Error(`${schema.type} unsupported`)
   }
@@ -34,6 +38,10 @@ function build (schema) {
   return (new Function(code))()
 }
 
+function $asNull (i) {
+  return 'null'
+}
+
 function $asNumber (i) {
   var num = Number(i)
   if (isNaN(num)) {
@@ -78,6 +86,11 @@ function buildObject (schema, code, name) {
     `
 
     switch (type) {
+      case 'null':
+        code += `
+          json += $asNull()
+        `
+        break
       case 'string':
         code += `
           json += $asString(obj.${key})

test.js

@@ -84,3 +84,20 @@ buildTest({
     something: 'else'
   }
 })
+
+buildTest({
+  'title': 'null',
+  'type': 'null'
+}, null)
+
+buildTest({
+  'title': 'with null',
+  'type': 'object',
+  'properties': {
+    'firstName': {
+      'type': 'null'
+    }
+  }
+}, {
+  firstName: null
+})