[pro] Lexer wanted

[Marc Battyani]

The original question was about a lexer do use with buffalo. PEG parsers
do the equivalent of yacc + lex but it should be possible to use a PEG
parser to do only the lexer part to use with buffalo.
Optima (and optima.ppcre) is another library that can be used for lexers.

Marc

On 2/14/15 17:31, Paul Tarvydas wrote:
> I wish that I’d had PEG 20 years ago,
>
> PEG parses a wider set of grammars than YACC can.
>
> PEG is backtracking, but, it uses a trick, memoizing, that minimizes the cost of backtracking.
>
> Given the hardware we have these days, I don’t see why anyone would use anything but PEG and packrat parsing.
>
> Google phrase “bryan ford peg”
>
> Building a PEG parser is way, way easier than dealing with Lex and YACC.
>
> I’m not sure if I’ve answered all of your questions … please feel free to ask again....
>
> pt
>
>
>
>> On Feb 14, 2015, at 4:47 PM, Gary King <garywarrenking at gmail.com> wrote:
>>
>> Hi Paul,
>>
>> What is the performance of Esrap vis-a-vis something like cl-yac? Given a BN grammar, how hard is it to build up a PEG parser?
>>
>> thanks,
>>
>>
>>> On Feb 13, 2015, at 10:04 AM, Paul Tarvydas <paultarvydas at gmail.com> wrote:
>>>
>>> Esrap is a PEG parser.  PEG is Lex and Yacc combined.  I'm sure that you could use esrap as a lexer-only, if you wish to.
>>>
>>> http://nikodemus.github.io/esrap/
>>>
>>> On my github there's an experimental PEG syntax overlaid over esrap syntax, if you care.  https://github.com/guitarvydas
>>>
>>> Ping me if you need ref's to papers about PEG.
>>>
>>> pt
>>>
>>>
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>> --
>> Gary Warren King, metabang.com 
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>>
>>
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