Allow to specify includeFile position.

[andyli]

Currently haxe.macro.Compiler.includeFile() includes the input file into the call site, where is usually inside __init__. It is problematic:

Problem 1. unable to include strict-mode incompatible file

Haxe by default generate JS output in strict mode. But the input file (e.g. jQuery!) may not be strict mode compatible, thus there will be run-time error being thrown.

Promlem 2. unable to extend classes from the included file

Since the haxe class members are defined before __init__s, we cannot extend an external class. Example:

// external.js
var External = function() { };

extern class External {
    static function __init__():Void {
        haxe.macro.Compiler.includeFile("external.js");
    }
}

class Test extends External {
    static function main():Void {
        trace("ok");
    }
}

JS output:

// Generated by Haxe
(function (console) { "use strict";
function $extend(from, fields) {
    function Inherit() {} Inherit.prototype = from; var proto = new Inherit();
    for (var name in fields) proto[name] = fields[name];
    if( fields.toString !== Object.prototype.toString ) proto.toString = fields.toString;
    return proto;
}
var Test = function() { };
Test.main = function() {
    console.log("ok");
};
Test.__super__ = External;
Test.prototype = $extend(External.prototype,{
});
// external.js
var External = function() { };
Test.main();
})(typeof console != "undefined" ? console : {log:function(){}});

run-time error:

/Users/andy/Documents/workspace/TestHaxe/Test.js:14
Test.prototype = $extend(External.prototype,{
                                 ^
TypeError: Cannot read property 'prototype' of undefined
    at console.undefined.log (/Users/andy/Documents/workspace/TestHaxe/Test.js:14:34)
    at Object.<anonymous> (/Users/andy/Documents/workspace/TestHaxe/Test.js:19:3)
    at Module._compile (module.js:456:26)
    at Object.Module._extensions..js (module.js:474:10)
    at Module.load (module.js:356:32)
    at Function.Module._load (module.js:312:12)
    at Function.Module.runMain (module.js:497:10)
    at startup (node.js:119:16)
    at node.js:929:3
Error: Command failed with error 8

This PR

This PR adds an argument position to includeFile. It is defaulted to Top, which is the top of the output, outside our top-level closure. The JS output of the above example will become:

// Generated by Haxe
// external.js
var External = function() { };
(function (console) { "use strict";
function $extend(from, fields) {
    function Inherit() {} Inherit.prototype = from; var proto = new Inherit();
    for (var name in fields) proto[name] = fields[name];
    if( fields.toString !== Object.prototype.toString ) proto.toString = fields.toString;
    return proto;
}
var Test = function() { };
Test.main = function() {
    console.log("ok");
};
Test.__super__ = External;
Test.prototype = $extend(External.prototype,{
});
Test.main();
})(typeof console != "undefined" ? console : {log:function(){}});

[dionjwa]

+1 This will be really useful.