Thanks guys :-) * Nicolas Pouillard [2009-01-03 16:39:59 +0100]:

Excerpts from Xie Hanjian's message of Sat Jan 03 16:28:30 +0100 2009:

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Hi,

I tried this in ghci:

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Prelude> 1:2:[] == 1:2:[] True

Does this mean (:) return the same object on same input, or (==) is not for identity checking? If the later is true, how can I check two object is the *same* object?

Here (==) is the structural equality. There is generally no exposed function to check for identity of values. This would expose too much of the memory model and the compilation process to give a specification to such a function.

-- Nicolas Pouillard

-- jan=callcc{|jan|jan};jan.call(jan)