[Haskell-beginners] Syntax of Complex

[Shishir Srivastava]

Hi,

The Data.Complex package defines the new data type 'Complex' as

----------

data Complex a  = !a :+ !a

-------

Where ':+' is an infix operator. I don't however understand the usage of
'!' in front of the type variable 'a'. What exactly is the purpose of '!' ?

Any help would be appreciated.

Thanks,
Shishir Srivastava
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