Re: [Haskell-beginners] Parse string with optional entries [Parsec]

On Mon, Aug 8, 2011 at 6:39 AM, wrote:

Hi all,

I'm trying to parse a string in one of the following forms using Parsec:

"1\t1\t123\t456" -> desired output: [Just 1, Just 1, Just 123, Just 456]

or

"1\t\1\t\t456"  -> desired output: [Just 1, Just 1, Nothing, Just 456]

i.e., the input is a list of numbers, separated by '\t' characters, with the possibility of missing entries. I'm having troubles with the backtracking in case of missing numbers. Can anybody give me a hint?

What do you have so far?

Thanks in advance, Stefan

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