preprocessor
Version:
Preprocessor.js: A JavaScript source file preprocessor, e.g. to build different versions of a library.
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Markdown
===========================================
Provides a JavaScript source file preprocessor, e.g. to build different versions of a library. It's for example used to
build [ProtoBuf.js](https://github.com/dcodeIO/ProtoBuf.js) (its [build](https://github.com/dcodeIO/ProtoBuf.js/blob/master/build.js)
and [main script](https://github.com/dcodeIO/ProtoBuf.js/blob/master/src/ProtoBuf.js) are quite good examples).
Directives
----------
* Includes (always relative to the `baseDirectory`, defaults to "."):
```javascript
...
// #include "path/to/file.js"
...
```
* Static conditions:
```javascript
// #ifdef FULL
console.log("Including extension");
// #include "path/to/extension.js"
// #else
console.log("Not including extension");
// #endif
```
* Inverse static conditions:
```javascript
// #ifndef FULL
console.log("Not including extension");
// #else
console.log("Including extension");
// #include "path/to/extension.js"
// #endif
```
* Evaluable conditions:
```javascript
// #if 1==2
console.log("1==2");
// #elif 2==2
console.log("2==2");
// #endif
```
* Inline variables and functions:
```js
// #define var PI=Math.PI
// #define function RADTODEG(x){return x*180/PI}
var angle = // #put RADTODEG(3)+";"
```
* Writing the result of evaluated expressions:
```javascript
var version = // #put '"'+VERSION+'";"'
var str = // #put "\"Hello world!\";"
var onePlusOne = // #put (1+1)+";"
```
Features
--------
* [CommonJS](http://www.commonjs.org/) compatible
* [RequireJS](http://requirejs.org/)/AMD compatible
* Shim compatible (include the script, then use var ByteBuffer = dcodeIO.ByteBuffer;)
* [node.js](http://nodejs.org) compatible, also available via [npm](https://npmjs.org/package/preprocessor)
* [Closure Compiler](https://developers.google.com/closure/compiler/) ADVANCED_OPTIMIZATIONS compatible (fully annotated,
`Preprocessor.min.js` has been compiled this way, `Preprocessor.min.map` is the source map)
* Fully documented using [jsdoc3](https://github.com/jsdoc3/jsdoc)
* Well tested through [nodeunit](https://github.com/caolan/nodeunit)
* Zero production dependencies
* Small footprint
Command line utility
--------------------
Install via npm: `npm -g install preprocessor`
#### Command line ####
Usage: `preprocess sourceFile [baseDirectory] [-myKey[=myValue], ...] [> outFile]`
```bash
preprocess Source.js . -FULL=true > Source.full.js
```
API
---
The API is quite simple:
```javascript
var result = new Preprocessor(
mainFileSource,
baseDirectoryOrIncludes
).process(defines);
```
with `baseDirectoryOrIncludes` being either a string containing the path to the base directory or an object of included
sources by filename. When running in a browser, only the later is supported.
#### node.js / CommonJS ####
```javascript
var Preprocessor = require("preprocessor");
var source = "..."; // e.g. through fs.readFile
var pp = new Preprocessor(source, ".");
console.log(pp.process({
FULL: true
}));
```
#### RequireJS / AMD ####
```javascript
require(["/path/to/Preprocessor.js"], function(Preprocessor) {
var source = "..."; // e.g. through fs.readFile / $.ajax
var pp = new Preprocessor(source, ".");
console.log(pp.process({
FULL: true
}));
});
```
#### Browser / shim ####
**Note:** To use the `#include` directive in the browser, do not specify the base directory but an object of included
sources by filename:
```html
<script src="//raw.github.com/dcodeIO/Preprocessor.js/master/Preprocessor.min.js"></script>
```
```javascript
var Preprocessor = dcodeIO.Preprocessor;
var source = "..."; // e.g. through. $.ajax
var pp = new Preprocessor(source, {
"./includes/extension.js": "var myVar = 2;" // <- #include "includes/extension.js"
});
alert(pp.process({
FULL: true
}));
```
Using includes instead of a base directory like shown in the example above is supported regardless of the platform you
are on.
Downloads
---------
* [ZIP-Archive](https://github.com/dcodeIO/Preprocessor.js/archive/master.zip)
* [Tarball](https://github.com/dcodeIO/Preprocessor.js/tarball/master)
Documentation
-------------
* [View documentation](http://htmlpreview.github.com/?http://github.com/dcodeIO/Preprocessor.js/master/docs/Preprocessor.html)
Tests (& Examples) [](https://travis-ci.org/dcodeIO/Preprocessor.js)
------------------
* [View source](https://github.com/dcodeIO/Preprocessor.js/blob/master/tests/suite.js)
* [View report](https://travis-ci.org/dcodeIO/Preprocessor.js)
License
-------
Apache License, Version 2.0 - http://www.apache.org/licenses/LICENSE-2.0.html