"unexpected end of input, expecting end of input" about parsec

[samuela]

Here's another way to trigger this:

passports = sepBy1 passport (try (endOfLine *> endOfLine *> pure ()) <|> (endOfLine *> eof *> pure ()))

which gets rid of the new-line option:

❯ ./day4.hs
Left "(poop)" (line 1134, column 1):
unexpected end of input
expecting end of input, "byr", "cid", "eyr", "ecl", "hgt", "hcl", "iyr" or "pid"

[phadej]

Read http://blog.ezyang.com/2014/05/parsec-try-a-or-b-considered-harmful/

By trying too much you make parsecs life harder.

[phadej]

In particular, removing try from sepBy1Try seems to fix the problem and not break the parser.

[samuela]

That's fair, but it feels like this error message falls into the category of things that "should never happen".