1 #!/usr/bin/env python 2 3 """ 4 Character-related functions. 5 6 Copyright (C) 2015, 2016, 2017 Paul Boddie <paul@boddie.org.uk> 7 8 This program is free software; you can redistribute it and/or modify it under 9 the terms of the GNU General Public License as published by the Free Software 10 Foundation; either version 3 of the License, or (at your option) any later 11 version. 12 13 This program is distributed in the hope that it will be useful, but WITHOUT 14 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS 15 FOR A PARTICULAR PURPOSE. See the GNU General Public License for more 16 details. 17 18 You should have received a copy of the GNU General Public License along with 19 this program. If not, see <http://www.gnu.org/licenses/>. 20 """ 21 22 from __builtins__.types import check_int, check_string 23 from native import str_chr, unicode_unichr 24 25 def chr(i): 26 27 "Return a string containing a character having the value 'i'." 28 29 check_int(i) 30 31 if 0 <= i <= 255: 32 return str_chr(i) 33 else: 34 raise ValueError, i 35 36 _hexdigits = "0123456789abcdef" 37 38 def _base(number, base, prefix=""): 39 40 """ 41 Return 'number' encoded in the given 'base', prefixed with 'prefix'. 42 """ 43 44 if number < 0: 45 number = -number 46 sign = "-" 47 else: 48 sign = "" 49 50 digits = [] 51 52 if number: 53 while number: 54 digits.append(_hexdigits[number % base]) 55 number = number / base 56 else: 57 digits.append("0") 58 59 digits.append(prefix) 60 61 if sign: 62 digits.append(sign) 63 64 return "".join(reversed(digits)) 65 66 def hex(number, prefix="0x"): 67 68 """ 69 Return 'number' encoded as a hexadecimal (base 16) value, prefixed with 70 'prefix' ("0x" by default). 71 """ 72 73 return _base(number, 16, prefix) 74 75 def oct(number, prefix="0"): 76 77 """ 78 Return 'number' encoded as an octal (base 8) value, prefixed with 'prefix' 79 ("0" by default). 80 """ 81 82 return _base(number, 8, prefix) 83 84 def ord(c): 85 86 "Return the value of the given character 'c'." 87 88 return c.__ord__() 89 90 def unichr(i): 91 92 "Return the given character value 'i' encoded as a character." 93 94 check_int(i) 95 96 if 0 <= i <= 2097151: 97 return utf8string(unicode_unichr(i)) 98 else: 99 raise ValueError, i 100 101 # vim: tabstop=4 expandtab shiftwidth=4