mirror of
https://github.com/Mercury-Language/mercury.git
synced 2026-04-22 12:53:47 +00:00
435 lines
11 KiB
Mathematica
435 lines
11 KiB
Mathematica
%---------------------------------------------------------------------------%
|
|
% Copyright (C) 1994-1998 The University of Melbourne.
|
|
% This file may only be copied under the terms of the GNU Library General
|
|
% Public License - see the file COPYING.LIB in the Mercury distribution.
|
|
%---------------------------------------------------------------------------%
|
|
%-----------------------------------------------------------------------------%
|
|
|
|
% File: char.m.
|
|
% Main author: fjh.
|
|
% Stability: high.
|
|
|
|
% This module defines some predicates that manipulate characters.
|
|
|
|
% Originally we used `character' rather than `char' for the type name
|
|
% because `char' was used by NU-Prolog to mean something different.
|
|
% But now we use `char' and the use of `character' is discouraged.
|
|
|
|
%-----------------------------------------------------------------------------%
|
|
%-----------------------------------------------------------------------------%
|
|
|
|
:- module char.
|
|
:- interface.
|
|
|
|
%-----------------------------------------------------------------------------%
|
|
|
|
:- type char == character.
|
|
|
|
:- pred char__to_int(char, int).
|
|
:- mode char__to_int(in, out) is det.
|
|
:- mode char__to_int(in, in) is semidet. % implied
|
|
:- mode char__to_int(out, in) is semidet.
|
|
% Convert a character to it's corresponding numerical code.
|
|
|
|
:- pred char__max_char_value(int).
|
|
:- mode char__max_char_value(out) is det.
|
|
% Returns the maximum numerical character code.
|
|
|
|
:- pred char__min_char_value(int).
|
|
:- mode char__min_char_value(out) is det.
|
|
% Returns the minimum numerical character code.
|
|
|
|
:- pred char__to_upper(char, char).
|
|
:- mode char__to_upper(in, out) is det.
|
|
% Convert a character to uppercase.
|
|
|
|
:- pred char__to_lower(char, char).
|
|
:- mode char__to_lower(in, out) is det.
|
|
% Convert a character to lowercase.
|
|
|
|
:- pred char__lower_upper(char, char).
|
|
:- mode char__lower_upper(in, out) is semidet.
|
|
:- mode char__lower_upper(out, in) is semidet.
|
|
% char__lower_upper(Lower, Upper) is true iff
|
|
% Lower is a lower-case letter and Upper is the corresponding
|
|
% upper-case letter.
|
|
|
|
:- pred char__is_whitespace(char).
|
|
:- mode char__is_whitespace(in) is semidet.
|
|
% True iff the character is whitespace, i.e. a space, tab,
|
|
% newline, carriage return, form-feed, or vertical tab.
|
|
|
|
:- pred char__is_upper(char).
|
|
:- mode char__is_upper(in) is semidet.
|
|
% True iff the character is an uppercase letter.
|
|
|
|
:- pred char__is_lower(char).
|
|
:- mode char__is_lower(in) is semidet.
|
|
% True iff the character is a lowercase letter.
|
|
|
|
:- pred char__is_alpha(char).
|
|
:- mode char__is_alpha(in) is semidet.
|
|
% True iff the character is a letter.
|
|
|
|
:- pred char__is_alnum(char).
|
|
:- mode char__is_alnum(in) is semidet.
|
|
% True iff the character is a letter or digit.
|
|
|
|
:- pred char__is_alpha_or_underscore(char).
|
|
:- mode char__is_alpha_or_underscore(in) is semidet.
|
|
% True iff the character is a letter or an underscore.
|
|
|
|
:- pred char__is_alnum_or_underscore(char).
|
|
:- mode char__is_alnum_or_underscore(in) is semidet.
|
|
% True iff the character is a letter, a digit or an underscore.
|
|
|
|
:- pred char__is_digit(char).
|
|
:- mode char__is_digit(in) is semidet.
|
|
% True iff the character is a decimal digit (0-9).
|
|
|
|
:- pred char__is_binary_digit(char).
|
|
:- mode char__is_binary_digit(in) is semidet.
|
|
% True iff the character is a binary digit (0 or 1).
|
|
|
|
:- pred char__is_octal_digit(char).
|
|
:- mode char__is_octal_digit(in) is semidet.
|
|
% True iff the character is a octal digit (0-7).
|
|
|
|
:- pred char__is_hex_digit(char).
|
|
:- mode char__is_hex_digit(in) is semidet.
|
|
% True iff the character is a hexadecimal digit (0-9, a-f, A-F).
|
|
|
|
:- pred char__digit_to_int(char, int).
|
|
:- mode char__digit_to_int(in, out) is semidet.
|
|
% Succeeds if char is a decimal digit (0-9) or letter (a-z or A-Z).
|
|
% Returns the character's value as a digit (0-9 or 10-35).
|
|
|
|
:- pred char__int_to_digit(int, char).
|
|
:- mode char__int_to_digit(in, out) is semidet.
|
|
:- mode char__int_to_digit(out, in) is semidet.
|
|
% char__int_to_uppercase_digit(Int, DigitChar):
|
|
% True iff `Int' is an integer in the range 0-35 and
|
|
% `DigitChar' is a decimal digit or uppercase letter
|
|
% whose value as a digit is `Int'.
|
|
|
|
:- pred char__det_int_to_digit(int, char).
|
|
:- mode char__det_int_to_digit(in, out) is det.
|
|
% Returns a decimal digit or uppercase letter corresponding to the
|
|
% value.
|
|
% Calls error/1 if the integer is not in the range 0-35.
|
|
|
|
%-----------------------------------------------------------------------------%
|
|
%-----------------------------------------------------------------------------%
|
|
|
|
:- implementation.
|
|
:- import_module require.
|
|
|
|
char__is_whitespace(' ').
|
|
char__is_whitespace('\t').
|
|
char__is_whitespace('\n').
|
|
char__is_whitespace('\r').
|
|
char__is_whitespace('\f').
|
|
char__is_whitespace('\v').
|
|
|
|
char__is_alpha(Char) :-
|
|
( char__is_lower(Char) ->
|
|
true
|
|
; char__is_upper(Char) ->
|
|
true
|
|
;
|
|
fail
|
|
).
|
|
|
|
char__is_alnum(Char) :-
|
|
( char__is_alpha(Char) ->
|
|
true
|
|
; char__is_digit(Char) ->
|
|
true
|
|
;
|
|
fail
|
|
).
|
|
|
|
char__is_alpha_or_underscore(Char) :-
|
|
( Char = '_' ->
|
|
true
|
|
;
|
|
char__is_alpha(Char)
|
|
).
|
|
|
|
% We explicitly enumerate here for efficiency.
|
|
% (this predicate is part of the inner loop of the lexer.)
|
|
char__is_alnum_or_underscore(Char) :-
|
|
( Char = '0'
|
|
; Char = '1'
|
|
; Char = '2'
|
|
; Char = '3'
|
|
; Char = '4'
|
|
; Char = '5'
|
|
; Char = '6'
|
|
; Char = '7'
|
|
; Char = '8'
|
|
; Char = '9'
|
|
; Char = 'a'
|
|
; Char = 'b'
|
|
; Char = 'c'
|
|
; Char = 'd'
|
|
; Char = 'e'
|
|
; Char = 'f'
|
|
; Char = 'g'
|
|
; Char = 'h'
|
|
; Char = 'i'
|
|
; Char = 'j'
|
|
; Char = 'k'
|
|
; Char = 'l'
|
|
; Char = 'm'
|
|
; Char = 'n'
|
|
; Char = 'o'
|
|
; Char = 'p'
|
|
; Char = 'q'
|
|
; Char = 'r'
|
|
; Char = 's'
|
|
; Char = 't'
|
|
; Char = 'u'
|
|
; Char = 'v'
|
|
; Char = 'w'
|
|
; Char = 'x'
|
|
; Char = 'y'
|
|
; Char = 'z'
|
|
; Char = 'A'
|
|
; Char = 'B'
|
|
; Char = 'C'
|
|
; Char = 'D'
|
|
; Char = 'E'
|
|
; Char = 'F'
|
|
; Char = 'G'
|
|
; Char = 'H'
|
|
; Char = 'I'
|
|
; Char = 'J'
|
|
; Char = 'K'
|
|
; Char = 'L'
|
|
; Char = 'M'
|
|
; Char = 'N'
|
|
; Char = 'O'
|
|
; Char = 'P'
|
|
; Char = 'Q'
|
|
; Char = 'R'
|
|
; Char = 'S'
|
|
; Char = 'T'
|
|
; Char = 'U'
|
|
; Char = 'V'
|
|
; Char = 'W'
|
|
; Char = 'X'
|
|
; Char = 'Y'
|
|
; Char = 'Z'
|
|
; Char = '_'
|
|
).
|
|
% A more consise implementation is:
|
|
% ( char__is_digit(Char) ->
|
|
% true
|
|
% ;
|
|
% char__is_alpha_or_underscore(Char)
|
|
% ).
|
|
|
|
char__is_lower(Lower) :-
|
|
char__lower_upper(Lower, _).
|
|
|
|
char__is_upper(Upper) :-
|
|
(
|
|
char__lower_upper(_, Upper)
|
|
->
|
|
true
|
|
;
|
|
fail
|
|
).
|
|
|
|
char__to_lower(Char, Lower) :-
|
|
(
|
|
char__lower_upper(LowerChar, Char)
|
|
->
|
|
Lower = LowerChar
|
|
;
|
|
Lower = Char
|
|
).
|
|
|
|
char__to_upper(Char, Upper) :-
|
|
(
|
|
char__lower_upper(Char, UpperChar)
|
|
->
|
|
Upper = UpperChar
|
|
;
|
|
Upper = Char
|
|
).
|
|
|
|
%-----------------------------------------------------------------------------%
|
|
|
|
% Lots of big tables.
|
|
%
|
|
% It's conceivable that there are more efficient implementations,
|
|
% but these versions are very portable.
|
|
|
|
%-----------------------------------------------------------------------------%
|
|
|
|
char__is_binary_digit('0').
|
|
char__is_binary_digit('1').
|
|
|
|
char__is_octal_digit('0').
|
|
char__is_octal_digit('1').
|
|
char__is_octal_digit('2').
|
|
char__is_octal_digit('3').
|
|
char__is_octal_digit('4').
|
|
char__is_octal_digit('5').
|
|
char__is_octal_digit('6').
|
|
char__is_octal_digit('7').
|
|
|
|
char__is_digit('0').
|
|
char__is_digit('1').
|
|
char__is_digit('2').
|
|
char__is_digit('3').
|
|
char__is_digit('4').
|
|
char__is_digit('5').
|
|
char__is_digit('6').
|
|
char__is_digit('7').
|
|
char__is_digit('8').
|
|
char__is_digit('9').
|
|
|
|
char__is_hex_digit('0').
|
|
char__is_hex_digit('1').
|
|
char__is_hex_digit('2').
|
|
char__is_hex_digit('3').
|
|
char__is_hex_digit('4').
|
|
char__is_hex_digit('5').
|
|
char__is_hex_digit('6').
|
|
char__is_hex_digit('7').
|
|
char__is_hex_digit('8').
|
|
char__is_hex_digit('9').
|
|
char__is_hex_digit('a').
|
|
char__is_hex_digit('b').
|
|
char__is_hex_digit('c').
|
|
char__is_hex_digit('d').
|
|
char__is_hex_digit('e').
|
|
char__is_hex_digit('f').
|
|
char__is_hex_digit('A').
|
|
char__is_hex_digit('B').
|
|
char__is_hex_digit('C').
|
|
char__is_hex_digit('D').
|
|
char__is_hex_digit('E').
|
|
char__is_hex_digit('F').
|
|
|
|
%-----------------------------------------------------------------------------%
|
|
|
|
char__det_int_to_digit(Int, Digit) :-
|
|
( char__int_to_digit(Int, Digit1) ->
|
|
Digit = Digit1
|
|
;
|
|
error("char__int_to_digit failed")
|
|
).
|
|
|
|
char__int_to_digit(0, '0').
|
|
char__int_to_digit(1, '1').
|
|
char__int_to_digit(2, '2').
|
|
char__int_to_digit(3, '3').
|
|
char__int_to_digit(4, '4').
|
|
char__int_to_digit(5, '5').
|
|
char__int_to_digit(6, '6').
|
|
char__int_to_digit(7, '7').
|
|
char__int_to_digit(8, '8').
|
|
char__int_to_digit(9, '9').
|
|
char__int_to_digit(10, 'A').
|
|
char__int_to_digit(11, 'B').
|
|
char__int_to_digit(12, 'C').
|
|
char__int_to_digit(13, 'D').
|
|
char__int_to_digit(14, 'E').
|
|
char__int_to_digit(15, 'F').
|
|
char__int_to_digit(16, 'G').
|
|
char__int_to_digit(17, 'H').
|
|
char__int_to_digit(18, 'I').
|
|
char__int_to_digit(19, 'J').
|
|
char__int_to_digit(20, 'K').
|
|
char__int_to_digit(21, 'L').
|
|
char__int_to_digit(22, 'M').
|
|
char__int_to_digit(23, 'N').
|
|
char__int_to_digit(24, 'O').
|
|
char__int_to_digit(25, 'P').
|
|
char__int_to_digit(26, 'Q').
|
|
char__int_to_digit(27, 'R').
|
|
char__int_to_digit(28, 'S').
|
|
char__int_to_digit(29, 'T').
|
|
char__int_to_digit(30, 'U').
|
|
char__int_to_digit(31, 'V').
|
|
char__int_to_digit(32, 'W').
|
|
char__int_to_digit(33, 'X').
|
|
char__int_to_digit(34, 'Y').
|
|
char__int_to_digit(35, 'Z').
|
|
|
|
char__digit_to_int(Digit, Int) :-
|
|
( char__lower_upper(Digit, Upper) ->
|
|
char__int_to_digit(Int, Upper)
|
|
;
|
|
char__int_to_digit(Int, Digit)
|
|
).
|
|
|
|
%-----------------------------------------------------------------------------%
|
|
|
|
:- char__lower_upper(X, Y) when X or Y.
|
|
|
|
char__lower_upper('a', 'A').
|
|
char__lower_upper('b', 'B').
|
|
char__lower_upper('c', 'C').
|
|
char__lower_upper('d', 'D').
|
|
char__lower_upper('e', 'E').
|
|
char__lower_upper('f', 'F').
|
|
char__lower_upper('g', 'G').
|
|
char__lower_upper('h', 'H').
|
|
char__lower_upper('i', 'I').
|
|
char__lower_upper('j', 'J').
|
|
char__lower_upper('k', 'K').
|
|
char__lower_upper('l', 'L').
|
|
char__lower_upper('m', 'M').
|
|
char__lower_upper('n', 'N').
|
|
char__lower_upper('o', 'O').
|
|
char__lower_upper('p', 'P').
|
|
char__lower_upper('q', 'Q').
|
|
char__lower_upper('r', 'R').
|
|
char__lower_upper('s', 'S').
|
|
char__lower_upper('t', 'T').
|
|
char__lower_upper('u', 'U').
|
|
char__lower_upper('v', 'V').
|
|
char__lower_upper('w', 'W').
|
|
char__lower_upper('x', 'X').
|
|
char__lower_upper('y', 'Y').
|
|
char__lower_upper('z', 'Z').
|
|
|
|
%-----------------------------------------------------------------------------%
|
|
|
|
:- pragma c_code(char__to_int(Character::in, Int::out), will_not_call_mercury, "
|
|
Int = (UnsignedChar) Character;
|
|
").
|
|
|
|
:- pragma c_code(char__to_int(Character::in, Int::in), will_not_call_mercury, "
|
|
SUCCESS_INDICATOR = ((UnsignedChar) Character == Int);
|
|
").
|
|
|
|
:- pragma c_code(char__to_int(Character::out, Int::in), will_not_call_mercury,
|
|
"
|
|
/*
|
|
** If the integer doesn't fit into a char, then
|
|
** the assignment `Character = Int' below will truncate it.
|
|
** SUCCESS_INDICATOR will be set to true only if
|
|
** the result was not truncated.
|
|
*/
|
|
Character = Int;
|
|
SUCCESS_INDICATOR = ((UnsignedChar) Character == Int);
|
|
").
|
|
|
|
% We used unsigned character codes, so the minimum character code
|
|
% is always zero.
|
|
|
|
char__min_char_value(0).
|
|
|
|
:- pragma c_header_code("#include <limits.h>").
|
|
:- pragma c_code(char__max_char_value(Max::out), will_not_call_mercury, "
|
|
Max = UCHAR_MAX;
|
|
").
|
|
|
|
%-----------------------------------------------------------------------------%
|