http://notes.underscorediscovery.com/haxe-entry-point/

build.hxml

#use this class as our entry point
-main HaxelibCounter

#generate a neko file from the code
-neko run.n

#use the arguable lib as a dependency
-lib arguable

#specify the define, which we can comment out to disable
-D haxelibcounter_verbose

#execute our new file with neko to test it immediately
-cmd neko run.n

final_build.hxml

#use this class as our entry point
-main HaxelibCounter

#is this a debug build? leave this line enabled
#-debug

#generate a neko file from the code
-neko run.n

#use the arguable lib as a dependency
-lib arguable

#specify the define, which we can comment out to disable
#-D haxelibcounter_verbose

#execute our new file with neko to test it immediately
-cmd neko run.n --count --show-names

final_HaxelibCounter.hx

import arguable.ArgParser;

using StringTools;

class HaxelibCounter {

        //The main entry point
    static function main() {

        var args = ArgParser.parse( Sys.args() );

        print('haxelibcounter');

        debug('> found args $args');

        if(args.length == 0) {
            return usage();
        }

        if(args.has('count')) {
            return do_count(args);
        }

    } //main

    static function usage() {
        print('usage:');
        print('   --count | displays the number of haxelib libraries installed');
        print('   --show-names | must be specified with --count, lists installed haxelibs one per line');
    }

    static function do_count(args) {

            //call `haxelib list` and read the output:
        var process = new sys.io.Process('haxelib',['list']);
        var result = process.stdout.readAll().toString();

        debug('> haxelib list returned a ${result.length} length string');

        if(result.length > 0) {

                //split the list up by each line
            var items = result.split('\n');

                //remove any blank items from the list, in case haxelib adds empty lines
            items = items.filter(function(item) return item.length > 0);

                //we know how many there are now
            print('${items.length} haxelibs installed!');

                //now we can handle the additional flag
            if(args.has('show-names')) {

                var item_names = items.map(function(item) return item.split(': ')[0]);
                for(name in item_names) print('  $name');

            }

        } else {
            print('An unknown error occured. `haxelib list` was not able to be called, it returned status ${process.exitCode()}');
        }

    } //do_count

//Internal

    static function print(value) {
        #if debug trace(value);
        #else Sys.println(value);
        #end
    }

    static function debug(value) {
        #if haxelibcounter_verbose
            trace(value);
        #end
    }

} //HaxelibCount

haxelib.json

{
  "name": "haxelibcounter",
  "url" : "https://github.com/underscorediscovery/haxe-entry-point-example/",
  "license": "MIT",
  "tags": ["cross"],
  "description": "Haxe entry point - An article on getting started with Haxe",
  "version": "1.0.0",
  "releasenote": "Initial version",
  "contributors": ["underscorediscovery"]
}

O1.hx

> haxelib run haxelibcounter
HaxelibCounter.hx:69: haxelibcounter  
HaxelibCounter.hx:76: > found args { any => true, length => 0, valid => [], invalid => [{ name => /Users/sven/dev/haxe-entry-point-example/, value =>  }] }  
HaxelibCounter.hx:69: usage:  
HaxelibCounter.hx:69:     --count | displays the number of haxelib libraries installed  
HaxelibCounter.hx:69:     --show-names | must be specified with --count, lists installed haxelibs one per line  

O2.hx

HaxelibCounter.hx:68: > found args { any => true, length => 1, valid => [{ name => count, value =>  }], invalid => [] }
HaxelibCounter.hx:68: > haxelib list returned a 1409 length string
HaxelibCounter.hx:48: 42 haxelibs installed!

O3.hx

haxelib run haxelibcounter --count --show-names
haxelibcounter
43 haxelibs installed!
  actuate
  arguable
  box2d
  ...

O4.hx

> haxelib install arguable  
Downloading arguable-1,0,2.zip...  
Download complete : 12071 bytes in 0.2s (47.7KB/s)  
  Install .gitignore
  Install README.md
  Created arguable/
  Install arguable/ArgParser.hx
  Install arguable/Stack.hx
  Install haxelib.json
  Created test/
  Install test/Test.hx
  Install test/TestArguable.n
  Install test/build.hxml
  Current version is now 1.0.2
Done  

P0.hx

static function main() {  
    
    var args = ArgParser.parse( Sys.args() );
    
    debug('> found args $args');
    
    if(args.length == 0) {
        return usage();
    }
    
    if(args.has('count')) {
        return do_count(args);
    }
    
} //main


static function usage() {  
    trace('haxelibcounter usage:');
    trace('   --count | displays number of haxelib libraries installed');
    trace('   --show-names | must be specified with --count, lists installed haxelibs one per line');
}

P1.hx

static function do_count(args) {

        //call `haxelib list` and read the output:
    var process = new sys.io.Process('haxelib',['list']);
    var result = process.stdout.readAll().toString();

    debug('> haxelib list returned a ${result.length} length string');

    if(result.length > 0) {

            //split the list up by each line
        var items = result.split('\n');

            //remove any blank items from the list, in case haxelib adds empty lines
        items = items.filter(function(item) return item.length > 0);

            //we know how many there are now
        trace('${items.length} haxelibs installed!');
        
            //:todo: handle --show-names

    } else {
        trace('An unknown error occured. `haxelib list` was not able to be called, it returned status ${process.exitCode()}');
    }

} //do_count

P2.hx

    //we know how many there are now
trace('${items.length} haxelibs installed!');

    //now we can handle the additional flag
if(args.has('show-names')) {

    var item_names = items.map(function(item) return item.split(': ')[0]);
    for(name in item_names) print('  $name');

}

P3.hx

static function debug(value) {  
    #if haxelibcounter_verbose
        trace(value);
    #end
}

P4.hx

static function print(value) {  
    #if debug trace(value);
    #else Sys.println(value);
    #end
}