How to read fastly files ( I/O operation)

[bioinfornatics]

On Thursday, 7 February 2013 at 14:42:57 UTC, monarch_dodra wrote:
> On Thursday, 7 February 2013 at 14:30:11 UTC, bioinfornatics 
> wrote:
>> Little feed back
>> i named f the f's script and monarch the monarch's script
>>
>> gdmd -O -w -release f.d
>> ~ $ time ./f bigFastq.fastq
>> ['T':999786820, 'A':1007129068, 'N':39413, 'C':1350576504, 
>> 'G':1353023772]
>>
>> real	2m14.966s
>> user	0m47.168s
>> sys	0m15.379s
>> ~ $ gdmd -O -w -release monarch.d
>> monarch.d:117: no identifier for declarator Lines
>> monarch.d:117: alias cannot have initializer
>> monarch.d:130: identifier or integer expected, not assert
>>
>>
>> i haven't take the time to look more
>>
>> but in any case it seem memory mapped file is really slowly 
>> whereas it is said that is the faster way to read file. Create 
>> an index where reading the file need 12 min that is useless as 
>> for read and compute you need 2 min
>
> You must be using dmd 2.060. I'm using some 2.061 features: 
> Namelly "new style alias".
>
> Just change line 117:
> alias Lines = typeof(File.init.byLine());
> to
> alias typeof(File.init.byLine()) Lines;
>
> As for 130, it's a "version(assert)" eg, code that does not get 
> executed in release. Just remove the "version(assert)", if it 
> gets executed, it is not a big deal.
>
> In any case, I think the code is mostly "proof", I wouldn't use 
> it as is.
>
> ------------
>
> BTW, I've started working on my library. How would users expect 
> the "quality" format served? As an array of characters, or as 
> an array of integrals (ubytes)?

ubyte as is a number is maybe easier to understand an cuttoff 
some value