Re: [Ocaml-lib-devel] IO.input / Lexing.lexbuf

[Bardur A. <sp...@sc...>]

Nicolas Cannasse wrote:
>> A recent project required me to parse gzipped XML files using Xml-Light.
>>  The most convenient way to access the gzipped files was using Extlib's
>> Unzip.inflate on an IO.input stream.  However, since Xml-Light does not
>> support IO or the standard OO file interface (it only supports input
>> from files, Pervasives streams, strings, and lexbufs), it was necessary
>> to define a wrapper function:
>>
>>   let lexbuf_of_input i =
>>     Lexing.from_function
>>       (fun s n ->
>>         try
>>           IO.input i s 0 n
>>         with IO.No_more_input ->
>>           0);;
>>
>> I just wonder whether it might be worth adding a couple of conversion
>> functions along these lines to the IO module, since I can imagine them
>> being generally useful?  The code is trivial, but one of the things I
>> value Extlib for is that it reduces the need for boilerplate like this.
> 
> Hi Peter,
> 
> The only problem is that this would create an IO -> Lexing dependency. 
> OCaml performs linkage on a per-module basis so not sure it's nice to 
> add such an overweight for a single simple function.
> 

That reminds me... At one point I also wanted to add 
"input_of_file_descr" and "output_of_file_descr" to the IO module. In 
fact, I'd still be interested in adding these.

Could we maybe add a new "IO_extras" module for such 
not-strictly-needed-but-nice-to-have functionality?

-- 
Bardur Arantsson
<bar...@TH...>

- Ouch! That's going to bleed when my heart beats.
                                  Professor Farnsworth, 'Futurama'