I've Just Liberated My Modules

Re:I've Just Liberated My Modules by chvid on Tuesday March 22, 2016 @09:28PM (#11341428)

You need to go something like:

  module.exports = function leftpad (str, len, ch) { return Array(Math.max(0, len - String(str).length)).join(ch || ' ') + String(str); };

Unfortunately we need to wrap str twice so maybe a one-liner is not quite in place.

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Re:I've Just Liberated My Modules by vespakoen on Tuesday March 22, 2016 @10:16PM (#11341646)

The array + join is slower

http://jsperf.com/leftpadtesting

Repeat + slice is too

http://jsperf.com/leftpad

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Re:I've Just Liberated My Modules by vespakoen on Tuesday March 22, 2016 @10:00PM (#11341570)

So this I guess

module.exports = function leftpad (str, len, ch) { str = String(str); if (ch === 0) { ch = '0'; } return Array(Math.max(0, len - str.length)).join(ch || ' ') + str; };

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Re:I've Just Liberated My Modules by vespakoen on Tuesday March 22, 2016 @09:53PM (#11341543)

Cool, I like the Math.max. Two liner then str = String(str);\n...

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Re:I've Just Liberated My Modules by chvid on Tuesday March 22, 2016 @10:01PM (#11341579)

And I did not notice the 0 check in the original code either :-D

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Re:I've Just Liberated My Modules by gsb on Tuesday March 22, 2016 @09:52PM (#11341534)

Also, this doesn't support zero padding with ch=0.

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