make the new operator optional before the JSZip constructor
#93
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This line of code implements John Resig's self-calling constructor pattern. See also: http://ejohn.org/blog/simple-class-instantiation/ http://habrahabr.ru/post/135027/
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@Mithgol Nice ! Could you add an unit test for this constructor ? We already have one for current constructor. And I agree with you, this leads to a new minor version. @Stuk should I prepare a v2.1.1 (with only #91) first / in parallel ? I think #91 is a bit urgent (as the installation fails behind a restrictive firewall) but we could wait to have more stuff for the v2.2.0. What do you think of it ? |
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@dduponchel a quick v2.1.1 with #91 sounds good to me |
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I'm preparing it ! |
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I can see the version 2.1.1 in npm registry. I have tested it, it works great! |
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I've just added a test; it passed on Travis CI. |
| @@ -59,6 +59,9 @@ test("JSZip", function(){ | |||
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| var zip = new JSZip(); | |||
| ok(zip, "Constructor works"); | |||
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| var zipNoNew = JSZip(); | |||
| ok(zipNoNew.file, "Constructor adds `new` before itself where necessary"); | |||
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I think these tests would be more explicit if changed to ok(zip instanceof JSZip, ...). Would you mind doing that?
make the `new` operator optional before the `JSZip` constructor
See Stuk#93 for more informations.
As @qlqllu has reported, an attempt to shorten JSZip call (giving it the form
var jsZIP = new require('jszip')()) fails.The failure's cause is a well-known JavaScript's operator precedence (the operator
newhas higher precedence than a function call — even if Node'srequireis that function). However, frankly speaking, that precedence in this case looks counter-intuitive to me as well.This case reminded me of John Resig's self-calling constructor pattern (given in Resig's blog entry Simple “Class” Instantiation in 2007). Nobody uses
new $with Resig's jQuery and, I think, JSZip might follow jQuery's example and benefit from it.This pull request makes the
newoperator optional before JSZip's constructor. Programmers might continue usingnewor omit it, depending on their inner personal preferences:new+ space) might feel more RAD and less boilerplate code;newmight serve as a reminder that a constructor call is ahead;someZIP = require('jszip')()instead ofsomeZIP = new (require('jszip'))()means less brackets;(Unlike the example in Resig's blog, this pull request refrains from using
arguments.calleebecause the use of that property is believed to slow down the engine.)This change introduces a new backwards-compatible feature. An
npm publishof a new minor version is recommended.