How can I convert a JavaScript for-loop to CoffeeScript?

Question

for (i = 0; i < 10; i++) {      doStuff();  } 

That's the JavaScript code that I Want to convert to CoffeeScript.

Answer 1

doStuff() for i in [0 .. 9] 

This is explained on the introduction page: http://coffeescript.org/#loops

Edit/Update by JP:

The exact translation is:

doStuff() for i in [0...10] 

You need to be careful with the ".." vs "...", for example:

count = 0 doStuff() for i in [0..count] #still executes once! 

So you think, no problem... I'll just loop until count-1!

count = 0 doStuff() for i in [0..count-1] #executes twice!! '0' and then '-1' 

Literal translation of:

for (var i = 0; i < someCount; ++i)   doStuff() 

is

for i in [0...someCount]   doStuff()    

Answer 2

The marked answer is functionaly correct but the generated code doesn't match the original javascript.
The right way (read, the one closest to the following javascript)

for (i = 0; i < 10; i++) {   doStuff(); } 

is doStuff() for i in [0..someCount] by 1 Note the by 1 on the for loop.

Now this code, still creates an extra _i variable. If you can't live with it, then use the following:

i=0 while i<=someCount   doStuff()   i++