add a 'length operator': #some_array

[blitmap]

Hi. To put it short: I'm from Lua. In Lua we have the '#' operator to basically return the .length of an array. Arrays in Javascript are just objects with number keys -- in Lua this is the same, but the # length operator actually returns an internal/private C member tracking the array part of a Lua table.

ANYWAY: I would love to see this operator brought to Coffeescript. Yes, I am biased -- I'm used to using #. I love Coffeescript and this suggestion is purely cosmetic -- I don't often need .length because of Coffeescript's for loop syntax, but for other object types I'd love to see those .length's disappear.

(Please and thank you?)

this: #some?.thing?.here?
becomes: (some !== undefined && some.thing !== undefined && some.thing.here !== undefined && some.thing.here.length)

I'll look into making a patch but I am pretty new to Coffeescript. I love it so far <3

[vendethiel]

# wouldn't work anyway - it's a comment for us.

[blitmap]

Yeah, forgot about that... better than // and /* */ for sure. :-)

I'm used to the valid characters for Lua identifiers, which is a much smaller set of characters than what JS (and Coffeescript) will allow.

I'd suggest :some_object as it looks almost like a range index, which might make people think of the length -- but it's not as clear as what Lua has with #some_object.

I dunno, I guess this suggestion can't work :3

[carlsmith]

I don't personally see the value of adding an entire operator for just getting the length of arrays. If you're doing it a lot in some part of you code, just alias it.

len = (a) -> a.length
length = len someArray

[ysmood]

It's sad to know that there are not enough operators for coffee to achieve it.

[carlsmith]

It's nothing to do with a lack of operators. If you have an operator for length, why not one for forEach and indexOf etc? We'll end up with KlingonScript.

[blitmap]

@carlsmith In Lua we just have # for quickly fetching the length of a table/hash/Object. We don't really lend ourselves to 'operator cancer'. len = (a) -> a.length works, but it's not as concise as just #1708

Oh well, # is more common as the comment prefix.... I don't hate it