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be08ab4736
Estimated hours taken: 1 Branches: main, release Add some synonyms for various functions in the string module and make some more general cleanups to parts of the standard library. library/array.m: s/applys/applies/ library/list.m: Position descriptive comments according to our coding standard. Fix a cut and paste error. list.foldl6 has six accumulators not five. library/parser.m: library/pqueue.m: library/set_bbbtree.m: library/set_ctree234.m: Fix minor formatting problems and spelling mistakes. library/string.m: Add functions string.from_int/1, string.from_char/1 and string.from_float/1 as synonyms for string.int_to_string/1 etc. library/version_types.m: s/incurrs/incurs/
46 lines
2.0 KiB
Mathematica
46 lines
2.0 KiB
Mathematica
%-----------------------------------------------------------------------------%
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% Copyright (C) 2004-2005 The University of Melbourne.
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% This file may only be copied under the terms of the GNU Library General
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% Public License - see the file COPYING.LIB in the Mercury distribution.
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% vim: ft=mercury ts=4 sw=4 et wm=0 tw=0
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%-----------------------------------------------------------------------------%
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% version_types.m
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% Ralph Becket <rafe@cs.mu.oz.au>
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% Fri Jul 9 15:31:16 EST 2004
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%
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% (This module only provides documentation describing general properties
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% of version types.)
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%
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% Version types are efficient pure implementations of typically imperative
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% structures, subject to the following caveat: efficient access is only
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% guaranteed for the "latest" version of a given structure. An older version
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% incurs an access cost proportional to the number of its descendants.
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%
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% For example, if A0 is a version array, and A1 is created by updating A0,
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% and A2 is created by updating A1, ..., and An is created by updating An-1,
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% then accesses to An cost O(1) (assuming no further versions of the array
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% have been created from An), but accesses to A0 cost O(n).
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%
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% Most of these data structures come with impure, unsafe means to "rewind"
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% to an earlier version, restoring that version's O(1) access times, but
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% leaving later versions undefined (i.e. only do this if you are discarding
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% all later versions of the structure.)
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%
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% The motivation for using version types is that they are ordinary ground
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% structures and do not depend upon uniqueness, while in many circumstances
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% offering similar levels of performance.
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%
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%-----------------------------------------------------------------------------%
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:- module version_types.
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:- interface.
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% This is just to stop the compiler complaining about this module
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% not defining anything.
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%
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:- type prevent_warning_about_empty_interface ---> dummy.
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%-----------------------------------------------------------------------------%
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%-----------------------------------------------------------------------------%
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