When creating objects or prototypes using Object.defineProperties or
Object.defineProperty it make your code look really verbose by all the
property descriptions that it needs. Most of the time, they are the same. They
either make your properties writable, readable or prevents them from being
enumerable. So basically:
Predefine makes Object.defineProperties your human readable and manageable.
npm install --save predefine
Let's start with a basic example of predefine usage:
var predefine = require('predefine');
function Base() {
var readable = predefine(this, { configurable: false, enumerable: false })
, writable = predefine(this, predefine.WRITABLE);
readable('prop', 'value');
writable('data', []);
}
Base.writable = predefine(Base.prototype, predefine.WRITABLE);
Base.writable('foo', 'bar');As you can see from the snippet above, it's really easy to see which properties are made readable and which one's are writable.
This allows you to add Backbone inspired .extend functionality to your
constructors. This makes inheriting a lot easier and readable. See the
extendible module in npm for information.
function Foo() {}
Foo.extend = predefine.extend;
var Bar = Foo.extend({
method: function () {}
});Test if a given object is a valid Object description to it can be used with
Object.defineProperty, Object.defineProperties and Object.create.
predefine.descriptor({ foo: 'bar' }); // false
predefine.descriptor({ value: 'bar' }); // true
predefine.descriptor({ value: 'bar', enumerable: false }); // true
predefine.descriptor({ value: 'bar', foo: 'bar' }); // falseThis is a simple helper function to create descriptions that can be used within
Object.create and Object.defineProperties.
var data = Object.create(null, predefine.create('foo', {
value: 'bar'
}));
var data = Object.create(null, predefine.create('foo', {
value: 'bar'
}, predefine.READABLE));
var data = Object.create(null, predefine.create('foo', 'bar', predefine.READABLE));Removes all enumerable properties from a given object, with the ability to keep white listed properties.
var data = { foo: 'bar', bar: 'foo' };
predefine.remove(data); // The data variable is now an empty object.
predefine.remove(data, ['foo']); // The foo property is kept.
var readable(data);
readable('baz', 'baz');
predefine.remove(data); // Only `baz` is left.Merge two objects in to one single object. This supports deep merging.
var result = predefine.merge({ foo: 'bar' }, { bar: 'foo' });Mixin two Objects, which also transfers properties that are set using Object.defineProperty.
var result = predefine.mixin({ foo: 'bar' }, { bar: 'foo' });MIT
![greenkeeper[bot] avatar](https://avatars.githubusercontent.com/in/505?v=4 "greenkeeper[bot]")
React
Typescript
Django
Laravel
Facebook
Microsoft
Google
Alibaba
D3
Tencent