Marpa-R2 2.077_011 <https://metacpan.org/release/JKEGL/Marpa-R2-2.077_011> installed successfully for me on cygwin and windows. The new HL interface is very appealing.
ASF.pod contains this passage: A symch is a series of alternatives (factorings) which share the same rule id. and the same glade. For this purpose, the *undef* of a token alternative is considered a rule ID. ... Recall that for this purpose, the token alternative's *undef* is considered a rule ID. s/undef/ID/? Or am I missing something? On Thu, Dec 19, 2013 at 7:57 AM, Jeffrey Kegler < [email protected]> wrote: > I have just uploaded Marpa-R2 > 2.077_011<https://metacpan.org/release/JKEGL/Marpa-R2-2.077_011>to CPAN. The > high-level ASF interface is now > documented<https://metacpan.org/pod/release/JKEGL/Marpa-R2-2.077_011/pod/ASF.pod>. > At the high-level, there's no talk of symches and factoring and memoization > is done for you. (OK, actually I do mention symches and factorings, but > it's all relegated to section at the end which you can skip.) You write a > "traverser" subroutine which is very like the action for of an AST node. > It has access to the rule ID, the literal input span, the values of the > child symbols, etc. Of course, the traverser has to deal with ambiguity, > and this motivates two differences: > > First, it's unified -- there is only one traverser subroutine. Instead of > multiple actions attached to rules, there's only one traverser and you'll > need to write your own if-else or similar logic to perform whatever > per-rule logic there is. This is because, due to ambiguity, each ASF glade > (the ASF equivalent of an AST's tree node) might involve several rules. > > Second, there's an iterator, $glade->next(). This lets you step through > the alternatives at a glade. > > It is still tree traversal, so it's not trivial, but I hope it's a less > daunting place to start than the low-level interface. > > -- jeffrey > > -- > 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/groups/opt_out. > -- 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/groups/opt_out.
