(Sorry, forgot to post these last week)
Luke:
- until last Wednesday, I worked on PGE in Perl 6
- then I worked on something completely unrelated
- PGE in Perl 6 now, barring the operator precedence parser, does
everything that the Parrot one does
- except for parsing rules
- but Audrey is doing that
c:
- does it produce match objects like PGE does?
Luke:
- yes
- last week I thought about things
- XQuery, tree matching
- pondering a data comprehension module for Perl 5
- whatever can make processing big, complex data structures quick and easy
- working with Audrey on context and coercion
- we have some disagreements about how that works
- mostly we're on the same page
- wrote a document describing pure MMD scheme
- including return type dispatch
- related to context
- those are in the Pugs repository
- I'll hack on them and then pass them along
Larry:
- did about 18 refactorings of the Perl 5 to Perl 5 translator
- ends up with a more adequately typed AST
Luke:
- typed how?
Larry:
- I'm not quite sure what I mean either
- a lot of the stuff internally to Perl is implicit
- there's no name for a particular node in the tree
- they happen accidentally
- we rearrange kids somehow and change a few flags and it applies
differently
- trying to name everything, or at least get close
- they're types in that sense
- it's not yet well-typed in the sense that I've looked at those names
and tried to figure out what's common between them
- it's nothing like PIL
- it's just trying to give a name to everything so we can have a hope at
translating at some point
- basically there are more node types currently than there are operator
ppcodes in Perl 5
- there's now a Statement, which doesn't really exist
- there's an opcode for transitioning into a statement in Perl 5
- but nothing really contains a statement
- that's a lot of the refactoring work
- make a more ordered tree
- now, of all the tests in the core modules, it translates more than 99.5%
correctly
- I haven't tried CPAN; I'd have to download it
- I also haven't bothered to try to hook this up to bleadperl
- I can probably delegate that eventually
- most of these refactorings come about due to thinking about what I need
to translate to Perl 6
- making sure that the information is there
- haven't actually tried to translate anything yet
- eventually I'll get up the courage to translate $foo[] to @foo[] and go
from there
- otherwise, thinking about what people say on the mailing lists
- admittedly not being very responsive to that
Allison:
- planning to take time off around Christmas to do development
- but I had my wisdom teeth out
- started working on expanding the Punie grammar again
- made it into sexpr part of the original perly.y
- ran into the traditional left recursion problem
- decided to use PGE's operator precedence parser instead
Luke:
- with regard to left recursion, there's a simple transform you can do
with closures to turn right-recursion data structures into ones that
look like left recursion
Allison:
- rather than doing left recursion, I flipped around
- broke it into two pieces
- the first element, and the rest of the expression
Luke:
- x [\+ x]* ?
Allison:
- expression matches
- expression = expression
- expression = expression + expression
- instead, say expression = term + rexpression
Luke:
- that's my biggest complaint about Parse::RecDescent
- it has a nice leftop which does that
- but then you get back a flat structure of all the matches you want
- I want a left recursive structure
- it's easier to parse things that look left-recursive
- you only have to handle two arguments, not N
- left-recursion transform might be nice in grammars, if it's generic...
Allison:
- for now, all I need in Perl 1 is operator precedence
- looks pretty cool so far
- I'll try to finish it off by the end of the day
- it'd be nice to have comments in the syntax of the independent grammar,
but...
Luke:
- my friend the crazy C++ programmer is trying to learn a new language
- I invited him to learn Perl 6
- I'm going to try to teach him Perl 6 without any past knowledge of
dynamic languages
