Re: alternatives to eval() for this case

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From	Thomas 'PointedEars' Lahn <PointedEars@web.de>
Newsgroups	comp.lang.javascript
Subject	Re: alternatives to eval() for this case
Date	Sat, 26 Sep 2015 09:33:01 +0200
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Joao Rodrigues wrote:

> On 25/09/15 14:26, Jay Braun wrote:
>> One of the few cases where eval() seems to be regarded as
>> acceptable is an AJAX case like this, where a script on the server
>> side is being requested:
> 
> There are other ways to insert a script into a document than using AJAX

More importantly, there are a lot *better* ways to do that.  One problem is 
that this does not work well in strict mode, where the eval scope chain is 
empty, and it does not work cross-origin without CORS.

> The problem, I think, is if you need the scripts to execute in an
> expected order. If so, you may try to mark the downloaded script as not
> async [1], using:
> 
> script.async = false;
> 
> [1] <http://caniuse.com/#feat=script-async>

If you read more carefully, you will realize that this does not work.  
“async=false” not only requires HTML5 support, but it is the *default* 
there:

<https://developer.mozilla.org/en-US/docs/Web/HTML/Element/script#Attributes> pp.

For scripts to be *executed* in a specific *order*, you need a promise-based 
approach like requireJS, where you define() the dependencies of a module, 
then require() it, and only when it has become available you (automagically) 
execute the code that depends on it.

<http://requirejs.org/>

-- 
PointedEars
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Thread

alternatives to eval() for this case Jay Braun <lyngwyst@gmail.com> - 2015-09-25 10:26 -0700
  Re: alternatives to eval() for this case Danny <dann90038@gmail.com> - 2015-09-25 15:39 -0700
    Re: alternatives to eval() for this case Jay Braun <lyngwyst@gmail.com> - 2015-09-25 15:50 -0700
  Re: alternatives to eval() for this case Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2015-09-26 00:35 -0300
    Re: alternatives to eval() for this case Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-09-26 09:33 +0200
  Re: alternatives to eval() for this case Jay Braun <lyngwyst@gmail.com> - 2015-09-26 20:14 -0700
    Re: alternatives to eval() for this case Martin Honnen <mahotrash@yahoo.de> - 2015-09-27 10:30 +0200
      Re: alternatives to eval() for this case Jay Braun <lyngwyst@gmail.com> - 2015-09-27 07:45 -0700

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