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Re: [Chicken-users] Alist versus Hash-table
From: |
John Cowan |
Subject: |
Re: [Chicken-users] Alist versus Hash-table |
Date: |
Tue, 12 Nov 2013 09:24:23 -0500 |
User-agent: |
Mutt/1.5.20 (2009-06-14) |
Peter Bex scripsit:
> alist-update will take O(n) to locate the key just like alist-update!,
> but when it finds the entry, it will need to build a new list with
> the entry replaced at the same position. That means it's O(n) to update
> (for new keys it's O(1), they can just be consed onto the front).
> In total, that's O(2n). The major extra time you see can not be
> explained due to that, but the output of time gives a clear hint.
Why was alist-update introduced, anyway? It is more efficient
to use either alist-update! or alist-cons (from SRFI 1) in any situation
I can think of. I note that neither SRFI 1 nor the alist-lib egg has it.
--
[W]hen I wrote it I was more than a little John Cowan
febrile with foodpoisoning from an antique carrot address@hidden
that I foolishly ate out of an illjudged faith http://ccil.org/~cowan
in the benignancy of vegetables. --And Rosta
- [Chicken-users] Alist versus Hash-table, Loïc Faure-Lacroix, 2013/11/12
- Re: [Chicken-users] Alist versus Hash-table, Christian Kellermann, 2013/11/12
- Re: [Chicken-users] Alist versus Hash-table, Jörg F. Wittenberger, 2013/11/12
- Re: [Chicken-users] Alist versus Hash-table, Peter Bex, 2013/11/12
- Re: [Chicken-users] Alist versus Hash-table, Loïc Faure-Lacroix, 2013/11/12
- Re: [Chicken-users] Alist versus Hash-table,
John Cowan <=
- Re: [Chicken-users] Alist versus Hash-table, Peter Bex, 2013/11/12
- Re: [Chicken-users] Alist versus Hash-table, John Cowan, 2013/11/12
- Re: [Chicken-users] Alist versus Hash-table, Peter Bex, 2013/11/12
- Re: [Chicken-users] Alist versus Hash-table, Loïc Faure-Lacroix, 2013/11/12
- Re: [Chicken-users] Alist versus Hash-table, John Cowan, 2013/11/12
- Re: [Chicken-users] Alist versus Hash-table, Peter Bex, 2013/11/13