FParsec list of string between special char

Question

When trying to parse {asdc,456,ghji,abc} and I run

run specialListParser "{asdc,456,ghji,abc}"

the parser fails with

The error occurred at the end of the input stream.
Expecting: any char not in ‘,’, ',' or '}'

I defined my parser based on this answer:

let str : Parser<_> = many1Chars (noneOf ",")
let comma = pstring ","
let listParser = sepBy str comma

let specialListParser = between (pstring "{") (pstring "}") listParser

What am I missing?

Please be more specific than "not working". What error message are you getting? Try implementing the test function from this section of the FParsec tutorial and run test specialListParser "{def,ghi,jkl}". What does it output? — rmunn
Basically, you haven't yet provided a minimal, complete and verifiable example to demonstrate your precise problem, and it's going to be hard to give you useful answers until you tell us more. — rmunn
Now that I see what your error message was, I was able to reproduce the problem myself, and fix it. — rmunn

rmunn rmunn · Accepted Answer · 2017-01-16T08:27:48

Looks like your str parser is consuming the final }, so that between never gets to see it. Change your str parser to be many1Chars (noneOf ",}") and it should work.

Alternately, noneOf [','; '}'] would also work, and might be more explicit about your intentions.

FParsec list of string between special char

1 Answers