[Haskell-cafe] Section Syntax Errors

David House dmhouse at gmail.com
Sat Nov 11 14:57:32 EST 2006

On 11/11/06, Aditya Siram <aditya_siram at hotmail.com> wrote:
> subOne :: [Integer] -> [Integer]
> subOne = map (- 1)

The short answer is that this is interpreted as negative unity, rather
than a section of binary minus. There are two common workarounds:

subOne = map (subtract 1)
subOne = map (+ (-1))

There's a whole minefield of opinions on whether this is the right
syntax or not. I'm sure you could google through the archives to
research this a bit more.

-David House, dmhouse at gmail.com

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