abbeycat/prepro

A tool to preprocess source files

prepro

prepro is a simple preprocessor, allowing for a set of centralised constant definitions to be substituted into a project's source files., _(*1)

Code Example

prepro requires two configuration files before it can be invoked - a definitions file, and a configuration file., _(*2)

Definitions

The definitions follows essentially a C-like syntax and identifies all constants (one per line) that prepro is to consider during preprocessing., _(*3)

The example below identifies a definitions file (prepro.def) that associates the constant "MAX_USERNAME_LENGTH" with the value "20":, _(*4)

; define an example constant
#define MAX_USERNAME_LENGTH 20

Configuration

The configuration file provides a simple mapping that tells prepro which file types it should look for, and what affix each constant will be surrounded by., _(*5)

The example below identifies a configuration file (prepro.ini) that implies prepro should only consider .php, .phtml, .js and .ini files for preprocessing, and that constants identified in prepro.def will be found with "__" affixes (i.e. "MAX_USERNAME_LENGTH" will be "__MAX_USERNAME_LENGTH__"):, _(*6)

[mappings]
php,phtml,js,ini = "__"

With the definitions and configuration available, prepro can be invoked against a source folder and told to output the preprocessed results into an output folder like this:, _(*7)

$ prepro --input pre --output source --config prepro.ini --preprocess prepro.def

Motivation

Some projects gather various technologies, frameworks and languages that operate across various layers. In these projects, certain constants can end up being defined repeatedly throughout, and changing them requires diligence to ensure all references have been captured and changed correctly., _(*8)

prepro moves to allow for a central definition of such constants, and to have these substituted at the source level (prior to any existing build process), helping to ensure that a change to a definition can be quickly, correctly and reliably propagated throughout the project., _(*9)

Installation

It is simplest to use Composer to download and install prepro., _(*10)

License

This project is licensed under MIT. See the LICENSE file for more details., _(*11)

Contribute

Contributions, whatever their nature, are welcomed., _(*12)