deepcopy didn't.  i haven't actually tried copy.  hang on...  [computer 
hangs; oom killer steps in].  nope!

On Tuesday, 21 July 2015 20:08:33 UTC-3, Jameson wrote:
>
> does `copy` work? although `bytestring` also seems like a good method for 
> this also. it seems wrong to me also that `match` is making a copy of the 
> original string (if that is indeed what it is doing)
>
> On Tue, Jul 21, 2015 at 6:57 PM andrew cooke <and...@acooke.org 
> <javascript:>> wrote:
>
>>
>> string(bytestring(...)) seems to do it.  would appreciate any more 
>> efficient solutions (and confirmation the analysis is correct - is this 
>> worth filing as an issue?)
>>
>>
>> On Tuesday, 21 July 2015 19:33:05 UTC-3, andrew cooke wrote:
>>>
>>>
>>> well, this was fun...  the following code rapidly triggers the OOM 
>>> killer on my machine (julia 0.4 trunk):
>>>
>>> s = repeat("a", 1000000)
>>> l = Any[]
>>> r = r"^\w"
>>>
>>> for i in 1:length(s)
>>>     m = match(r, s[i:end])
>>>     push!(l, m.match)
>>> end
>>>
>>> note that: (1) the regexp is only matching one character, so the array l 
>>> is at most a million characters long.
>>>
>>> what i think is happening (but this is only a guess) is that s[i:end] is 
>>> being passed though to the c level regexp library as a new string.  the 
>>> result (m.match) is then a substring into that.  because the substring is 
>>> kept around, the backing string cannot be collected.  and so there's an n^2 
>>> memory use.
>>>
>>> ideally, i don't think a new copy of the string should be passed to the 
>>> regexp engine.  maybe i am wrong?
>>>
>>> anyway, for now, if the above is right, i need some way to copy 
>>> m.match.  as far as i can tell string() doesn't help.  so what works?  or 
>>> am i wrong?
>>>
>>> thanks,
>>> andrew
>>>
>>

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