StrictData and the parser
Adam Sandberg Eriksson
adam at sandbergericsson.se
Thu Jun 4 19:52:02 UTC 2015
Hello *,
I'm working on the -XStrict language extension[1] for this years Google
summer of code. I've started with the smaller -XStrictData (as
documented at the wiki) and have the internals mostly figured out.
However after adding relevant rules for '~' in the parser[2] I get an
explosion of shift/reduce conflicts as well as 4 extra reduce/reduce
conflicts, see [3] for the happy info (the states with 36 shift/reduce
conflicts seem to be the problematic ones), I also fail to parse the
test file [4] with the error
DsStrictData.hs:15:1: error:
parse error (possibly incorrect indentation or mismatched brackets)
Can anyone offer some guidance on what the appropriate changes to the
parser are to make these "lazyness" marks work?
Thanks,
Adam
[1]: https://ghc.haskell.org/trac/ghc/wiki/StrictPragma
[2]:
https://github.com/adamse/ghc/blob/strict-pragma/compiler/parser/Parser.y#L1547-L1563
[3]:
https://gist.githubusercontent.com/adamse/8d6c54b6ae660fca8b97/raw/detailed-info
[4]:
https://github.com/adamse/ghc/blob/strict-pragma/testsuite/tests/deSugar/should_run/DsStrictData.hs#L13
--
Adam Sandberg Eriksson
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