Draft system schema.

Add multiple types example.

EXAMPLE.md

@@ -16,6 +16,7 @@ Table of Contents
       * [message-override](#message-override)
       * [message](#message)
       * [min](#min)
+      * [multiple-types](#multiple-types)
       * [multiple](#multiple)
       * [pattern](#pattern)
       * [placeholder](#placeholder)
@@ -444,6 +445,31 @@ schema.validate(source, function(err, res) {
 [ { [Error: func must have at least 1 arguments] field: 'func', reason: { id: 'min' } } ]
 ```
 
+#### multiple-types
+
+* [doc/example/multiple-types](https://github.com/freeformsystems/async-validate/blob/master/doc/example/multiple-types.js).
+
+```javascript
+// validate a field as one of multiple types
+var Schema = require('async-validate')
+  , descriptor = {
+      flag: {type: ['boolean', Boolean], required: true}
+    }
+  , source = {flag: 'foo'}
+  , schema;
+
+require('async-validate/plugin/all');
+
+schema = new Schema(descriptor);
+schema.validate(source, function(err, res) {
+  console.dir(res.errors);
+});
+```
+
+```
+[ { [Error: flag is not one of the allowed types boolean, Boolean] field: 'flag', reason: { id: 'type' } } ]
+```
+
 #### multiple
 
 * [doc/example/multiple](https://github.com/freeformsystems/async-validate/blob/master/doc/example/multiple.js).
@@ -701,7 +727,7 @@ schema.validate(source, opts, function(err, res) {
 ```
 
 ```
-[ { [Error: email: could not resolve dns for domain 1442468604548.com] field: 'email' } ]
+[ { [Error: email: could not resolve dns for domain 1442469859410.com] field: 'email' } ]
 ```
 
 #### type

doc/example/multiple-types.js

@@ -0,0 +1,14 @@
+// validate a field as one of multiple types
+var Schema = require('../..')
+  , descriptor = {
+      flag: {type: ['boolean', Boolean], required: true}
+    }
+  , source = {flag: 'foo'}
+  , schema;
+
+require('../../plugin/all');
+
+schema = new Schema(descriptor);
+schema.validate(source, function(err, res) {
+  console.dir(res.errors);
+});

system.js

@@ -0,0 +1,28 @@
+// schema for a schema definition
+var schema = {
+  type: 'object',
+  required: true,
+  fields: {
+    all: {
+      match: /./,
+      fields: {
+        additional: {type: 'boolean'},
+        list: {type: 'array'},
+        fields: {type: ['object', 'array']},
+        format: {type: 'string'},
+        len: {type: 'integer'},
+        min: {type: 'integer'},
+        max: {type: 'integer'},
+        pattern: {type: 'regexp'},
+        placeholder: {type: 'function'},
+        required: {type: 'boolean'},
+        test: {type: 'function'},
+        type: {type: ['string', 'function'], required: true},
+        values: {type: ['object', 'array']},
+        whitespace: {type: 'boolean'}
+      }
+    }
+  }
+}
+
+module.exports = schema;