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- # pseudomap
-
- A thing that is a lot like ES6 `Map`, but without iterators, for use
- in environments where `for..of` syntax and `Map` are not available.
-
- If you need iterators, or just in general a more faithful polyfill to
- ES6 Maps, check out [es6-map](http://npm.im/es6-map).
-
- If you are in an environment where `Map` is supported, then that will
- be returned instead, unless `process.env.TEST_PSEUDOMAP` is set.
-
- You can use any value as keys, and any value as data. Setting again
- with the identical key will overwrite the previous value.
-
- Internally, data is stored on an `Object.create(null)` style object.
- The key is coerced to a string to generate the key on the internal
- data-bag object. The original key used is stored along with the data.
-
- In the event of a stringified-key collision, a new key is generated by
- appending an increasing number to the stringified-key until finding
- either the intended key or an empty spot.
-
- Note that because object traversal order of plain objects is not
- guaranteed to be identical to insertion order, the insertion order
- guarantee of `Map.prototype.forEach` is not guaranteed in this
- implementation. However, in all versions of Node.js and V8 where this
- module works, `forEach` does traverse data in insertion order.
-
- ## API
-
- Most of the [Map
- API](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map),
- with the following exceptions:
-
- 1. A `Map` object is not an iterator.
- 2. `values`, `keys`, and `entries` methods are not implemented,
- because they return iterators.
- 3. The argument to the constructor can be an Array of `[key, value]`
- pairs, or a `Map` or `PseudoMap` object. But, since iterators
- aren't used, passing any plain-old iterator won't initialize the
- map properly.
-
- ## USAGE
-
- Use just like a regular ES6 Map.
-
- ```javascript
- var PseudoMap = require('pseudomap')
-
- // optionally provide a pseudomap, or an array of [key,value] pairs
- // as the argument to initialize the map with
- var myMap = new PseudoMap()
-
- myMap.set(1, 'number 1')
- myMap.set('1', 'string 1')
- var akey = {}
- var bkey = {}
- myMap.set(akey, { some: 'data' })
- myMap.set(bkey, { some: 'other data' })
- ```
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