Proposal: Applicative => Monad: Call for consensus

wren ng thornton wren at
Mon Jan 17 01:08:59 CET 2011

On 1/16/11 12:43 PM, Henning Thielemann wrote:
> Maciej Piechotka schrieb:
>> I agree that there are advantages of both ways and they are perfectly
>> compatible with each other. While I don't know about GHC internals I'd
>> assume that class v-tables (term borrowed from C++ I'm not sure about
>> Haskell terminology) is per-class and not copied for each function
>> invocation.
> "Method dictionary"

Perhaps I missed it, but I don't see anything in that page clarifying 
whether the actual underlying table is shared (i.e., the dictionary is 
just a pointer to a global table) or not (i.e., the dictionary is a 
constructed copy of the table). As far as the surface language is 
concerned the distinction doesn't matter, but as far as people worrying 
about performance considerations due to the size of dictionaries it does.

Live well,

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