1/*  Part of SWI-Prolog
    2
    3    Author:        Jan Wielemaker
    4    E-mail:        jan@swi-prolog.org
    5    WWW:           https://www.swi-prolog.org
    6    Copyright (c)  2026, SWI-Prolog Solutions b.v.
    7    All rights reserved.
    8
    9    Redistribution and use in source and binary forms, with or without
   10    modification, are permitted provided that the following conditions
   11    are met:
   12
   13    1. Redistributions of source code must retain the above copyright
   14       notice, this list of conditions and the following disclaimer.
   15
   16    2. Redistributions in binary form must reproduce the above copyright
   17       notice, this list of conditions and the following disclaimer in
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   19       distribution.
   20
   21    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   22    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   23    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
   24    FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
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   33*/
   34
   35:- module(uniname,
   36          [ unicode_name/2             % ?CodePoint, ?Name
   37          ]).   38:- use_foreign_library(foreign(uniname4pl)).   39
   40/** <module> Unicode character names
   41
   42This library relates  Unicode  code  points   to  their  formal  Unicode
   43character names (the `Name` property of `UnicodeData.txt`). It ships its
   44own compact UCD-derived table  (about  360   KB)  and  is independent of
   45library(unicode) and library(unicode_security).
   46
   47Algorithmic name ranges (Hangul syllables, CJK and Tangut ideographs and
   48the various ``PREFIX-<hex>`` families)  are   synthesised  from the code
   49point and carry no per-code-point storage;   the remaining ~34,600 names
   50are stored as a shared  word  table   plus  a  packed  token stream. See
   51``etc/gen_uniname.pl`` in the package directory  to regenerate the table
   52on a Unicode-version bump.
   53*/
   54
   55%!  unicode_name(?CodePoint:integer, ?Name:atom) is nondet.
   56%
   57%   True when Name is the Unicode character name of CodePoint.  Usage:
   58%
   59%     - `unicode_name(+CodePoint, -Name)` is semidet: the name of
   60%       CodePoint, failing when it has none (control, surrogate,
   61%       private-use or unassigned code points).
   62%     - `unicode_name(-CodePoint, +Name)` is semidet: the (unique)
   63%       code point with the given name.
   64%     - `unicode_name(-CodePoint, -Name)` is nondet: enumerate every
   65%       named code point on backtracking.
   66%
   67%   Name is an atom of the formal Unicode name in upper case, e.g.
   68%
   69%   ```
   70%   ?- unicode_name(0'A, N).
   71%   N = 'LATIN CAPITAL LETTER A'.
   72%
   73%   ?- unicode_name(C, 'EURO SIGN').
   74%   C = 8364.
   75%
   76%   ?- unicode_name(0xAC00, N).
   77%   N = 'HANGUL SYLLABLE GA'.
   78%   ```