utf8proc

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Version 1.1.3

- Added a function utf8proc_version returning a string containing the version number of the library.
- Included a target libutf8proc.dylib for MacOSX.
- PostgreSQL 8.3 compatibility (use of SET_VARSIZE macro)
author jbe
date Fri May 01 12:00:00 2009 +0200 (2009-05-01)
parents fcfd8c836c64
children 00d2bcbdc945
rev   line source
jbe@0 1
jbe@0 2 Please read the LICENSE file, which is shipping with this software.
jbe@0 3
jbe@0 4
jbe@0 5 *** QUICK START ***
jbe@0 6
jbe@0 7 For compilation of the C library call "make c-library", for compilation of
jbe@0 8 the ruby library call "make ruby-library" and for compilation of the
jbe@0 9 PostgreSQL extension call "make pgsql-library".
jbe@0 10
jbe@0 11 "make all" can be used to build everything, but both ruby and PostgreSQL
jbe@0 12 installations are required in this case.
jbe@0 13
jbe@9 14 For ruby there is alternatively provided a gem-file "utf8proc-1.1.3.gem".
jbe@4 15
jbe@0 16
jbe@0 17 *** GENERAL INFORMATION ***
jbe@0 18
jbe@7 19 The C library is found in this directory after successful compilation and
jbe@7 20 is named "libutf8proc.a" and "libutf8proc.so". The ruby library consists of
jbe@7 21 the files "utf8proc.rb" and "utf8proc_native.so", which are found in the
jbe@0 22 subdirectory "ruby/". The PostgreSQL extension is named "utf8proc_pgsql.so"
jbe@0 23 and resides in the "pgsql/" directory.
jbe@0 24
jbe@0 25 Both the ruby library and the PostgreSQL extension are built as stand-alone
jbe@0 26 libraries and are therefore not dependent the dynamic version of the
jbe@0 27 C library files, but this behaviour might change in future releases.
jbe@0 28
jbe@2 29 The Unicode version being supported is 5.0.0.
jbe@7 30 Note: Version 4.1.0 of Unicode Standard Annex #29 was used, as
jbe@7 31 version 5.0.0 had not been available yet.
jbe@0 32
jbe@0 33 For Unicode normalizations, the following options have to be used:
jbe@0 34 Normalization Form C: STABLE, COMPOSE
jbe@2 35 Normalization Form D: STABLE, DECOMPOSE
jbe@0 36 Normalization Form KC: STABLE, COMPOSE, COMPAT
jbe@2 37 Normalization Form KD: STABLE, DECOMPOSE, COMPAT
jbe@0 38
jbe@0 39
jbe@0 40 *** C LIBRARY ***
jbe@0 41
jbe@0 42 The documentation for the C library is found in the utf8proc.h header file.
jbe@0 43 "utf8proc_map" is most likely function you will be using for mapping UTF-8
jbe@0 44 strings, unless you want to allocate memory yourself.
jbe@0 45
jbe@0 46
jbe@0 47 *** RUBY API ***
jbe@0 48
jbe@0 49 The ruby library adds the methods "utf8map" and "utf8map!" to the String
jbe@0 50 class, and the method "utf8" to the Integer class.
jbe@0 51
jbe@0 52 The String#utf8map method does the same as the "utf8proc_map" C function.
jbe@0 53 Options for the mapping procedure are passed as symbols, i.e:
jbe@2 54 "Hello".utf8map(:casefold) => "hello"
jbe@0 55
jbe@7 56 The descriptions of all options are found in the C header file
jbe@7 57 "utf8proc.h". Please notice that the according symbols in ruby are all
jbe@7 58 lowercase.
jbe@0 59
jbe@0 60 String#utf8map! is the destructive function in the meaning that the string
jbe@0 61 is replaced by the result.
jbe@0 62
jbe@0 63 There are shortcuts for the 4 normalization forms specified by Unicode:
jbe@0 64 String#utf8nfd, String#utf8nfd!,
jbe@0 65 String#utf8nfc, String#utf8nfc!,
jbe@0 66 String#utf8nfkd, String#utf8nfkd!,
jbe@0 67 String#utf8nfkc, String#utf8nfkc!
jbe@0 68
jbe@0 69 The method Integer#utf8 returns a UTF-8 string, which is containing the
jbe@7 70 unicode char given by the code point.
jbe@0 71 0x000A.utf8 => "\n"
jbe@0 72 0x2028.utf8 => "\342\200\250"
jbe@0 73
jbe@0 74
jbe@0 75 *** POSTGRESQL API ***
jbe@0 76
jbe@7 77 For PostgreSQL there are two SQL functions supplied named "unifold" and
jbe@7 78 "unistrip". These functions function can be used to prepare index fields in
jbe@7 79 order to be folded in a way where string-comparisons make more sense, e.g.
jbe@7 80 where "bathtub" == "bath<soft hyphen>tub"
jbe@7 81 or "Hello World" == "hello world".
jbe@0 82
jbe@1 83 CREATE TABLE people (
jbe@1 84 id serial8 primary key,
jbe@1 85 name text,
jbe@1 86 CHECK (unifold(name) NOTNULL)
jbe@1 87 );
jbe@0 88 CREATE INDEX name_idx ON people (unifold(name));
jbe@0 89 SELECT * FROM people WHERE unifold(name) = unifold('John Doe');
jbe@0 90
jbe@7 91 The function "unistrip" removes character marks like accents or diaeresis,
jbe@7 92 while "unifold" keeps then.
jbe@7 93
jbe@7 94 NOTICE: The outputs of the function can change between releases, as
jbe@7 95 utf8proc does not follow a versioning stability policy. You have to
jbe@7 96 rebuild your database indicies, if you upgrade to a newer version
jbe@7 97 of utf8proc.
jbe@2 98
jbe@2 99
jbe@0 100 *** TODO ***
jbe@0 101
jbe@0 102 - detect stable code points and process segments independently in order to
jbe@0 103 save memory
jbe@0 104 - do a quick check before normalizing strings to optimize speed
jbe@0 105 - support stream processing
jbe@0 106
jbe@0 107
jbe@7 108 *** CONTACT ***
jbe@0 109
jbe@7 110 If you find any bugs or experience difficulties in compiling this software,
jbe@7 111 please contact me:
jbe@0 112
jbe@9 113 Project page: http://www.flexiguided.de/publications.utf8proc.en.html
jbe@9 114 Contact form: http://www.flexiguided.de/contactform.en.html
jbe@7 115
jbe@9 116 Jan Behrens
jbe@9 117

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