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A comment on Closure Compiler: a tool for making JavaScript download and run faster. Parent comment

Re:Closure Compiler: a tool for making JavaScript download a... by mythz on Monday August 31, 2015 @12:20PM (#10147517)
Have a look at the advanced compilation option: https://developers.google.com/closure/compiler/docs/api-tuto...

Basically when enabled it will rewrite normal property access, e.g: `myObj.foo` to something like `a.b` but wont shorten string literal access, e.g `myObj['foo']` just becomes `a.foo` which you would use for any API's you want to export.

For a real-world example I use string literals for declaring jquip's public API:

    p['removeAttr'] = function(name){
        return this['each'](function(){
          if (this.nodeType == 1) this.removeAttribute(name);
        });
    };
Which closure advanced rewrites to:

    q.removeAttr=function(a){return this.each(function(){this.removeAttribute(a)})};
Original: https://github.com/mythz/jquip/blob/master/dist/jquip.all.js

Compiled: https://github.com/mythz/jquip/blob/master/dist/jquip.all.cl...

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Re:Closure Compiler: a tool for making JavaScript download a... by sanderjd on Monday August 31, 2015 @01:08PM (#10147813)
How did it know it could leave out the `this.nodeType` check?
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Re:Closure Compiler: a tool for making JavaScript download a... by tomjen3 on Monday August 31, 2015 @01:51PM (#10148070)
If it can prove that it will always be 1 (ie by code not shown) it will be removed.
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Re:Closure Compiler: a tool for making JavaScript download a... by sanderjd on Monday August 31, 2015 @04:37PM (#10148950)
Yeah, I was curious how it could prove that in this specific case. Very neat, in any case.
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Re:Closure Compiler: a tool for making JavaScript download a... by nunull on Monday August 31, 2015 @12:32PM (#10147595)
May i ask why you are using this notation? I honestly can't think of any benefits. Isn't it more convenient and readable to use `p.removeAttr`?
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Re:Closure Compiler: a tool for making JavaScript download a... by mythz on Monday August 31, 2015 @12:44PM (#10147660)
My comment explains the entire purpose for using it - if I didn't, it would've got rewritten into `a.b` and none of the public API's would work!
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Re:Closure Compiler: a tool for making JavaScript download a... by eschutte2 on Monday August 31, 2015 @12:49PM (#10147684)
I wish there were a better way to indicate which properties were renameable, because I need this too and I'm not willing to go as far as you did.
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Re:Closure Compiler: a tool for making JavaScript download a... by greggman on Monday August 31, 2015 @01:15PM (#10147860)
You can tell it which properties to keep with `goog.exportSymbol()`
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Re:Closure Compiler: a tool for making JavaScript download a... by Shebanator on Monday August 31, 2015 @01:13PM (#10147854)
there is a much better way to deal with this:

https://developers.google.com/closure/compiler/docs/api-tuto...

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Re:Closure Compiler: a tool for making JavaScript download a... by eschutte2 on Monday August 31, 2015 @11:41PM (#10150598)
Thanks - I remember seeing that when looking through the docs, but I don't really like that either, unfortunately. I'm using Uglify right now, and I was thinking of adding a pre-minify step that walks the AST for a JSDoc-style annotation on either the properties themselves or a containing object, and pulls out the list of property names to preserve that way.
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