Usage of ! in a Haskell type

Posted by bjwbell on Stack Overflow See other posts from Stack Overflow or by bjwbell
Published on 2010-04-13T19:24:23Z Indexed on 2010/04/13 19:32 UTC
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haskell

In Alex the generated boilerplate code includes

data AlexPosn = AlexPn !Int  -- absolute character offset
                       !Int  -- line number
                       !Int  -- column number

What does the ! in front of the Int indicate?

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Developer IT

Usage of ! in a Haskell type - Developer IT

Usage of ! in a Haskell type

haskell

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