splitter for strings

[monarch_dodra via Digitalmars-d-learn]

On Monday, 9 June 2014 at 11:40:24 UTC, Chris wrote:
> On Monday, 9 June 2014 at 11:16:18 UTC, monarch_dodra wrote:
>> On Monday, 9 June 2014 at 11:04:12 UTC, Chris wrote:
>>> From the library reference:
>>>
>>> assert(equal(splitter("hello  world", ' '), [ "hello", "", 
>>> "world" ]));
>>>
>>> and
>>>
>>> "If a range with one separator is given, the result is a 
>>> range with two empty elements."
>>>
>>> My problem was that if I have input like
>>>
>>> auto word = "bla-";
>>>
>>> it will return parts.data.length == 2, so I would have to 
>>> check parts.data[1] != "". This is too awkward. I just want 
>>> the parts of the word, i.e.
>>>
>>> length == 2 // grab [0] grab [1]
>>> length == 1 // grab [0] (no second part, as in "bla-")
>>> length > 2 // do something else
>>
>> You can just pipe in an extra "filter!(a=>!a.empty)", and 
>> it'll do what you want:
>> put(parts, w.splitter('-').filter!(a=>!a.empty)());
>>
>> The rational for this behavior, is that it preserves the 
>> "total amount of information" from your input. EG:
>>
>> assert(equal(myString.spliter(sep).join(sep), myString));
>>
>> If the empty tokens were all stripped out, that wouldn't work, 
>> you'd have lost information about how many separators there 
>> actually were, and where they were.
>
> I see, I've already popped in a filter. I only wonder how much 
> of a performance loss that is. Probably negligible.

Arguably, none, since someone has to do the check anyways. If 
it's not done "outside" of splitter, it has to be done inside...