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Re: Source code "objectifying" technique?

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On 2013-01-03 11:34, JJ wrote:
> Sometimes I need some a library from the web, but its functions are all 
> globally defined instead of object based. For example:
> 
> var config=123;
> function abc(){
>   //does something
> }
> function def(){
>   //does something else
> }
> function ghi(a){
>   a=a||config;
>   abc(def(a));
> }
> function jkl(a){
>   a=a||config;
>   def(a);
> }
> 
> I want to put all those functions in a self contained object so that 
> accessing them would be like:
> 
> theLib.abc();
> theLib.ghi();
> theLib.abc();
> theLib.abc(456);

Okay, as long as you're aware of that calling abc() is _not_ the same
thing as calling theLib.abc(). At least make sure to check if any of the
functions use |this|.

> Usually I would convert each functions including all of the references 
> like below.
> 
> theLib={};
> theLib.config=123;
> theLib.abc=function(){
>   return theLib.config;
> }
> theLib.def=function(){
>   return theLib.config*10;
> }
> theLib.ghi=function(a){
>   a=a||theLib.config;
>   theLib.abc(theLib.def(a));
> }
> theLib.jkl=function(a){
>   a=a||theLib.config;
>   theLib.def(a);
> }
> 
> As you can see, this is a tedious work. Even for a 2KB code. Is there a 
> simpler way to do this?

Depends on the library, but something like this might work:

    var theLib = (function () {

      // -- start original lib content --
      var config = {...};
      function abc () {...}
      function def () {...}  // private helper
      function ghi () {...}
      // -- end original lib content --

      // this will be the public API of the library
      return {
         abc: abc,
         ghi: ghi,
         ...
      };

    })();

    theLib.abc(123);

Not every collection of functions can be contained in this way, but it
should work for your typical bunch-of-global-functions-because-
-the-author-doesn't-know-any-better library.


- stefan

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Thread

Source code "objectifying" technique? JJ <jaejunks@nah.meh> - 2013-01-03 10:34 +0000
  Re: Source code "objectifying" technique? Stefan Weiss <krewecherl@gmail.com> - 2013-01-03 19:32 +0100
    Re: Source code "objectifying" technique? JJ <jaejunks@nah.meh> - 2013-01-03 20:13 +0000
      Re: Source code "objectifying" technique? Stefan Weiss <krewecherl@gmail.com> - 2013-01-03 23:57 +0100
        Re: Source code "objectifying" technique? Stefan Weiss <krewecherl@gmail.com> - 2013-01-04 00:44 +0100
        Re: Source code "objectifying" technique? JJ <jaejunks@nah.meh> - 2013-01-04 02:00 +0000
  Re: Source code "objectifying" technique? Scott Sauyet <scott.sauyet@gmail.com> - 2013-01-03 10:37 -0800
    Re: Source code "objectifying" technique? Scott Sauyet <scott.sauyet@gmail.com> - 2013-01-03 10:43 -0800
    Re: Source code "objectifying" technique? JJ <jaejunks@nah.meh> - 2013-01-03 20:33 +0000
      Re: Source code "objectifying" technique? Scott Sauyet <scott.sauyet@gmail.com> - 2013-01-03 13:09 -0800
        Re: Source code "objectifying" technique? JJ <jaejunks@nah.meh> - 2013-01-04 02:33 +0000

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