Parsing integers [was: Re: [Haskell-cafe] help]

[Tim Chevalier]

On 12/9/07, Ryan Bloor <ryanbloor at hotmail.com> wrote:
>
> hi
>
> I have a function parseInt... which needs an error guard for when the input
> is not an Int.
>
> parseInt :: Parser
> parseInt [] = []
> parseInt xs = let (digits, rest) = span isDigit (removeSpace xs)
>                 in [(EInt (read digits), removeSpace rest)]
>
> Also... I have a function that does this... parseBinaryOp "+" "(5 + 2) if"
>    gives...[(Int 5, Int 2, "if")]
> so, op is '+' or "&&". I am unsure of how to begin...
>
> parseBinaryOp :: String -> String -> [(Expr, Expr, String)]
> parseBinaryOp op str
>

Check out:
http://www.haskell.org/haskellwiki/Homework_help

If this isn't homework, try posting again and phrasing your question
in the form of a question; saying "I am unsure of how to begin"
doesn't help us help you think about the problem.

Cheers,
Tim

-- 
Tim Chevalier * catamorphism.org * Often in error, never in doubt
"[Teaching children to read] will make America what we want it to be,
a literate country and a hopefuller country." -- George W. Bush