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Postings from March 2010
Nicholas Clark wrote: > On Tue, Mar 02, 2010 at 09:50:51AM -0600, David Nicol wrote: >> On Mon, Mar 1, 2010 at 12:43 PM, karl williamson >> <public@khwilliamson.com> wrote: >> >>> Inversion lists can be searched binarily. bsearch() is a standard C library >>> routine, but the only mention of it in Perl is in the POSIX module where it >>> says it is not furnished. This makes me think there must be a problem with >>> using the library routine. Is there? >> the problem is that you need to keep your data sorted, which is not >> perly. The perly thing to do is to keep data in a hash table instead >> of a sorted array. So not furnishing a perl interface to bsearch a >> perl array makes sense, because You Should Be Using A Hash Table Silly >> Rabbit. > > You're not understanding the problem here. > > What you say is appropriate for the general case in perl, but not for the > specific area that Karl is describing. > > Nicholas Clark > His point was that there's no gain in POSIX.pm having a bsearch, as someone writing in Perl will just use a hash. But then he started thinking about it some more, and sent me privately a possible reason to have a bsearch exposed to the Perl programmer, as in some cases it makes more sense to keep things in an array instead of a hash. mktables uses a binary search written in Perl, but it needs extra functionality beyond that which bsearch provides.Thread Previous | Thread Next