StrictData and the parser

Brandon Allbery allbery.b at
Thu Jun 4 20:06:52 UTC 2015

On Thu, Jun 4, 2015 at 3:52 PM, Adam Sandberg Eriksson <
adam at> wrote:

> 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)

Looks to me like it's confused about whether a ~ is part of an equality
constraint or is a laziness annotation. The former would be illegal at that
point, though, I'd think? Somewhere it believes a constraint might be
possible there, via btype.

As ezyang says in the message I see just came in, you'll need extra
production rules to distinguish that top level. Although I'd wonder why it
believes an equality constraint is acceptable there in the first place; is
that a lurking bug in the parser?

brandon s allbery kf8nh                               sine nomine associates
allbery.b at                                  ballbery at
unix, openafs, kerberos, infrastructure, xmonad
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