Here's a tutorial for small example of external lexing aka procedural parsing: http://jeffreykegler.github.io/Ocean-of-Awareness-blog/individual/2013/04/procedural.html
On Sat, Oct 15, 2016 at 4:12 AM, Harry <[email protected]> wrote: > Thanks, Jeffrey, for your responses. > > I've gone through the documentation of Marpa::R2::Scanless::R > <https://metacpan.org/pod/distribution/Marpa-R2/pod/Scanless/R.pod> but > it's not becoming fully clear how to 'connect' the external lexing routine > of mine to Marpa's built-in G1 parser. I've looked at some random Marpa > code on the Net but that code is looking way too complicated as far as > illustrating just the "external lexing" part goes. > > My expectation was (and, is) that of a bison/flex type of interface where > yyparse() calls yylex() to get the next token following which things > automatically work. With Marpa, it seems, you have to do (much?) more than > that (sorry, if I'm being inaccurate here). > > What I already understand: When doing external lexing, I assume I'll have > to create the equivalent of yylex() myself - in my case this function will, > e.g., be making heavy use of Perl Regex's. > > However, how would I pass the string value returned by my yylex() to Marpa > parser? > > Could someone please share a simple, "hello world" type of example, or if > not that, at least some pseudocode? > > > On Thursday, October 13, 2016 at 10:03:41 PM UTC+5:30, Jeffrey Kegler > wrote: >> >> 4.) Not sure this answers your question, but L0 rules allow full Marpa >> syntax. >> > > May I ask, why the full Perl Regex syntax is not supported in L0 rules? If > it were supported, I could've read a Java multi-line comment simply with > just this one-liner: > MultilineComment ~ ('/*' .*? '*/') # parentheses being optional > > > Regards, > /Harry > > > -- > You received this message because you are subscribed to the Google Groups > "marpa parser" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "marpa parser" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
