Fwd: Abandoning String = [Char]?
Performance will go utterly out the window if you use pattern synonyms
and the like to pretend that Text is [Char]. It would probably work
fine (great, even) when matching, but code that assumes String=[Char]
would be completely killed on the construction side, because building
Text by consing, or repeatedly prepending small chunks, is
ridiculously inefficient. These are the very things that are
*efficient* with [Char], and that people have assumed to be efficient
when writing code that uses it.
On May 22, 2015 5:58 PM, "Carter Schonwald"
one direction that this thread has *COMPLETELY* overlooked is the following:
could we use pattern synonyms or something along those lines to make the migration to Text or the like more seemless?
On Fri, May 22, 2015 at 9:30 PM, David Feuer
It would probably work fine (great, even) when matching, but code that assumes String=[Char] would be completely killed on the construction side, because building Text by consing, or repeatedly prepending small chunks, is ridiculously inefficient.
Actually, pattern-matching against Text using synonyms doesn't do so well performance-wise either. The unpack-on-the-left function is uncons, which has to do work and allocate memory.
participants (2)
-
Bryan O'Sullivan -
David Feuer