LoadFile_a.ahk

/*
    LoadFile(Path [, EXE])
    
        Loads a script file as a child process and returns an object
        which can be used to call functions or get/set global vars.
    
    Path:
          The path of the script.
    EXE:
          The path of the AutoHotkey executable (defaults to A_AhkPath).
    
    Requirements:
      - AutoHotkey v1.1.17+    http://ahkscript.org/download/
      - ObjRegisterActive      http://goo.gl/wZsFLP
      - CreateGUID             http://goo.gl/obfmDc

    Version: 1.0
*/

LoadFile(path, exe:="", exception_level:=-1) {
    ObjRegisterActive(client := {}, guid := CreateGUID())
    code =
    (LTrim
    LoadFile.Serve("%guid%")
    #include %A_LineFile%
    #include %path%
    )
    try {
        exe := """" (exe="" ? A_AhkPath : exe) """"
        exec := ComObjCreate("WScript.Shell").Exec(exe " /ErrorStdOut *")
        exec.StdIn.Write(code)
        exec.StdIn.Close()
        while exec.Status = 0 && !client._proxy
            Sleep 10
        if exec.Status != 0 {
            err := exec.StdErr.ReadAll()
            ex := Exception("Failed to load file", exception_level)
            if RegExMatch(err, "Os)(.*?) \((\d+)\) : ==> (.*?)(?:\s*Specifically: (.*?))?\R?$", m)
                ex.Message .= "`n`nReason:`t" m[3] "`nLine text:`t" m[4] "`nFile:`t" m[1] "`nLine:`t" m[2]
            throw ex
        }
    }
    finally
        ObjRegisterActive(client, "")
    return client._proxy
}

class LoadFile {
    Serve(guid) {
        try {
            client := ComObjActive(guid)
            client._proxy := new this.Proxy
            client := ""
        }
        catch ex {
            stderr := FileOpen("**", "w")
            stderr.Write(format("{} ({}) : ==> {}`n     Specifically: {}"
                , ex.File, ex.Line, ex.Message, ex.Extra))
            stderr.Close()  ; Flush write buffer.
            ExitApp
        }
        ; Rather than sleeping in a loop, make the script persistent
        ; and then return so that the #included file is auto-executed.
        Hotkey IfWinActive, %guid%
        Hotkey vk07, #Persistent, Off
        #Persistent:
    }
    class Proxy {
        __call(name, args*) {
            if (name != "G")
                return %name%(args*)
        }
        G[name] { ; x.G[name] because x[name] via COM invokes __call.
            get {
                global
                return ( %name% )
            }
            set {
                global
                return ( %name% := value )
            }
        }
        __delete() {
            ExitApp
        }
    }
}