Hugs for Macs different from Hugs for Suns ??

[Peter Padawitz]

Using the type definition:

 data Term a = T a [Term a]

I run the precomplied Hugs version on a Mac and another one under Sun OS.  
The first accepts the instance definition:

 instance Show (Term String) where ..

The second reports

 syntax error in instance head (variable expected)

and accepts if I write:

 instance Show a => Show (Term a) where ..

Why do the systems react differently???

Best regards,

	Peter

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Peter Padawitz
Informatik 5		
University of Dortmund 	
D-44221 Dortmund
Germany	
phone    	+49-231-755-5108
fax    	 	+49-231-755-4851 or -5802
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email	 	peter.padawitz@udo.edu