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Parser backtracking issues with nested arrays #2690
Description
http://try.purescript.org/?gist=e22c2b96c145d7c475ce4f26bc473704
render a =
[ Left "One"
, Right
[ Left "Two"
, { foo = 1 }
]
] Unable to parse module:
unexpected [
expecting , or ]
But if you remove the nesting, it's a better error
render a =
[ Left "Two"
, { foo = 1 }
] Unable to parse module:
unexpected =
expecting :, , or }
Activity
natefaubion commentedon Feb 23, 2017
Originally, the issue manifested for me with record binders in a case statement. But it seems to be an issue with nested arrays in general.
paf31 commentedon Mar 11, 2017
I've made multiple attempts to fix this, but all of them have involved non-trivial changes to the AST to avoid backtracking, and none of them have quite worked how I would like. I'm going to suggest this wait until we can move away from Parsec and towards something with better support for automatically left-factoring the grammar.
hdgarrood commentedon May 7, 2019
Now that the cst parser has been merged the error is better:
so I think this can be closed.