StrictData and the parser

Adam Sandberg Eriksson adam at
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?


Adam Sandberg Eriksson

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