On Sun, Nov 3, 2013 at 7:08 PM, Timothee Cour <[email protected]>wrote:

>
> On Sun, Nov 3, 2013 at 1:13 AM, Philippe Sigaud <[email protected]
> > wrote:
>
>>
>> My current plan is to write different engines, and letting either the
>> user select them at compile-time, or to have the parser decide which one to
>> use, depending on the grammar. I'm pretty sure the 'Type 3' parts of a
>> grammar (regular expressions) could be bone by using std.regex, for example.
>>
>
> even lexing can't be done with regex, eg nesting comments : /+ ... +/
> Also, although it may seem cleaner at first to combine lexing and parsing
> in 1 big grammar (as done in pegged), it usually is faster do feed a
> (separate) lexer output into parser.
>

Lexing, yes. I was imprecise: even in a context-free grammar, some rules
are regular and could use std.regex (the ct part) as the underlying engine,
just for that rule.

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