With SWI-Prolog when generating digits using
code_type(X,digit).
the result is the expected ASCII character codes and
178 (0xB2) ²
179 (0xB3) ³
185 (0xB9) ¹
e.g.
code_type(X,digit).
X = 48 ;
X = 49 ;
X = 50 ;
X = 51 ;
X = 52 ;
X = 53 ;
X = 54 ;
X = 55 ;
X = 56 ;
X = 57 ;
X = 178 ;
X = 179 ;
X = 185 ;
false.
How can I disable or change the functionality so that characters other than 0-9 are not a digit?
Obviously I can write a different routine, but I am wondering if there is not some option or statement to be executed that can do this.
TL;DR
Version
SWI-Prolog (Multi-threaded, 32 bits, Version 7.2.3)
SWI-Prolog Flags
current_prolog_flag(Name,Value).
query_debug_settings: debug(false,false)
save_history: true
debug: false
generate_debug_info: true
verbose_load: silent
emulated_dialect: swi
sandboxed_load: false
optimise: false
toplevel_var_size: 1000
allow_dot_in_atom: false
toplevel_prompt: ~m~d~l~! ?-
toplevel_print_anon: true
access_level: user
verbose_autoload: false
toplevel_extra_white_line: true
gui: true
timezone: 18000
verbose_file_search: false
char_conversion: false
history: 25
colon_sets_calling_context: true
verbose: normal
traditional: false
agc_margin: 10000
encoding: text
readline: false
break_level: 0
xpce: true
write_attributes: ignore
answer_format: ~p
quasi_quotations: true
bounded: false
min_tagged_integer: -16777216
integer_rounding_function: toward_zero
gmp_version: 5
xpce_version: 6.6.66
dde: true
gc: true
write_help_with_overstrike: false
user_flags: silent
address_bits: 32
max_tagged_integer: 16777215
allow_variable_name_as_functor: false
editor: pce_emacs
debug_on_error: true
shared_object_extension: dll
xpce_threaded: true
resource_database: c:/program files (x86)/swipl/boot32.prc
debugger_show_context: false
character_escapes: true
shared_object_search_path: PATH
iso: false
large_files: true
debugger_write_options: [quoted(true),portray(true),max_depth(10),attributes(portray),spacing(next_argument)]
pipe: true
c_cflags:
open_shared_object: true
threads: true
unload_foreign_libraries: false
home: c:/program files (x86)/swipl
prompt_alternatives_on: determinism
system_thread_id: 12492
dialect: swi
pid: 9796
executable: C:\Program Files (x86)\swipl\bin\swipl-win.exe
c_cc: gcc
last_call_optimisation: true
qcompile: false
warn_override_implicit_import: true
unknown: error
c_ldflags:
print_write_options: [portray(true),quoted(true),numbervars(true)]
c_libs:
c_libplso: -lswipl
max_arity: unbounded
report_error: true
trace_gc: false
autoload: true
answer_write_options: [quoted(true),portray(true),max_depth(10),spacing(next_argument)]
debug_term_position: false
back_quotes: codes
occurs_check: false
compile_meta_arguments: false
os_argv: [C:\Program Files (x86)\swipl\bin\swipl-win.exe,--win_app]
argv: []
emacs_inferior_process: false
cpu_count: 4
file_name_variables: false
color_term: true
version_data: swi(7,2,3,[])
hwnd: 924196
version_git: 7.2.3
console_menu: true
toplevel_residue_vars: false
double_quotes: string
stream_type_check: loose
windows: true
fileerrors: true
version: 70203
signals: true
arch: i386-win32
toplevel_print_factorized: false
compiled_at: Aug 25 2015, 13:45:56
tty_control: true
SWI-Prolog locale
current_locale(X).
X = default.
locale_property(X,Y).
X = default,
Y = alias(default) ;
X = default,
Y = decimal_point('.') ;
X = default,
Y = thousands_sep(',') ;
X = default,
Y = grouping([repeat(3)]).
Windows
Windows PowerShell
PS C:\> Get-UICulture
LCID Name DisplayName
---- ---- -----------
1033 en-US English (United States)
PS C:\> Get-CimInstance Win32_OperatingSystem | FL *
Status : OK
Name : Microsoft Windows 10 Pro|C:\WINDOWS|\Device\Harddisk0\Partition4
FreePhysicalMemory : 853644
FreeSpaceInPagingFiles : 7062504
FreeVirtualMemory : 2415552
Caption : Microsoft Windows 10 Pro
InstallDate : 8/4/2016 8:35:18 AM
CreationClassName : Win32_OperatingSystem
CSCreationClassName : Win32_ComputerSystem
CurrentTimeZone : -300
LastBootUpTime : 1/11/2017 1:41:34 PM
LocalDateTime : 1/14/2017 3:48:46 PM
MaxNumberOfProcesses : 4294967295
MaxProcessMemorySize : 137438953344
OSType : 18
Version : 10.0.14393
BuildNumber : 14393
BuildType : Multiprocessor Free
CodeSet : 1252
CountryCode : 1
DataExecutionPrevention_32BitApplications : True
DataExecutionPrevention_Available : True
DataExecutionPrevention_Drivers : True
DataExecutionPrevention_SupportPolicy : 2
Debug : False
Locale : 0409
Manufacturer : Microsoft Corporation
MUILanguages : {en-US}
OperatingSystemSKU : 48
Organization : Windows User
OSArchitecture : 64-bit
OSLanguage : 1033
OSProductSuite : 256
PortableOperatingSystem : False
Primary : True
ProductType : 1
ServicePackMajorVersion : 0
ServicePackMinorVersion : 0
SuiteMask : 272
SystemDirectory : C:\WINDOWS\system32
SystemDrive : C:
WindowsDirectory : C:\WINDOWS
Output
code_type(X,digit).
X = 48 ;
X = 49 ;
X = 50 ;
X = 51 ;
X = 52 ;
X = 53 ;
X = 54 ;
X = 55 ;
X = 56 ;
X = 57 ;
X = 178 ;
X = 179 ;
X = 185 ;
false.
X is 0'².
X = 178.
X is 0'³.
X = 179.
X is 0'¹.
X = 185.
code_type(47,digit).
false.
code_type(48,digit).
true.
code_type(0'0,digit).
true.
code_type(57,digit).
true.
code_type(58,digit).
false.
code_type(0'9,digit).
true.
code_type(177,digit).
false.
code_type(178,digit).
true.
code_type(179,digit).
true.
code_type(180,digit).
false.
code_type(184,digit).
false.
code_type(185,digit).
true.
code_type(186,digit).
false.
char_type(X,digit).
X = '0' ;
X = '1' ;
X = '2' ;
X = '3' ;
X = '4' ;
X = '5' ;
X = '6' ;
X = '7' ;
X = '8' ;
X = '9' ;
X = ² ;
X = ³ ;
X = ¹ ;
false.
What I tried/checked
2.4 Command line options
code_type/2
As char_type/2, but uses character codes rather than one-character atoms. Please note that both predicates are as flexible as possible. They handle either representation if the argument is instantiated and will instantiate only with an integer code or a one-character atom, depending of the version used. See also the Prolog flag double_quotes, atom_chars/2 and atom_codes/2.
char_type/2
Tests or generates alternative Types or Chars.
The character types are inspired by the standard C<ctype.h>primitives.char_type(?Char, ?Type)
digit - Char is a digit.
2.15.1.8 Unicode Prolog source
The SWI-Prolog Unicode character classification is based on version 6.0.0 of the Unicode standard. Please note that char_type/2 and friends, intended to be used with all text except Prolog source code, is based on the C library locale-based classification routines.
but didn't know how to find C library locale-based classification routines
I did a Google search using swi prolog code_type digit 178 however nothing that explains this shows up.
2.18 Wide character support
SWI-Prolog supports wide characters, characters with character codes above 255 that cannot be represented in a single byte. Universal Character Set (UCS) is the ISO/IEC 10646 standard that specifies a unique 31-bit unsigned integer for any character in any language. It is a superset of 16-bit Unicode, which in turn is a superset of ISO 8859-1 (ISO Latin-1), a superset of US-ASCII. UCS can handle strings holding characters from multiple languages, and character classification (uppercase, lowercase, digit, etc.) and operations such as case conversion are unambiguously defined.
ISO/IEC 10646 - Unicode 6.0
0030;DIGIT ZERO;Nd;0;EN;;0;0;0;N;;;;;
0031;DIGIT ONE;Nd;0;EN;;1;1;1;N;;;;;
0032;DIGIT TWO;Nd;0;EN;;2;2;2;N;;;;;
0033;DIGIT THREE;Nd;0;EN;;3;3;3;N;;;;;
0034;DIGIT FOUR;Nd;0;EN;;4;4;4;N;;;;;
0035;DIGIT FIVE;Nd;0;EN;;5;5;5;N;;;;;
0036;DIGIT SIX;Nd;0;EN;;6;6;6;N;;;;;
0037;DIGIT SEVEN;Nd;0;EN;;7;7;7;N;;;;;
0038;DIGIT EIGHT;Nd;0;EN;;8;8;8;N;;;;;
0039;DIGIT NINE;Nd;0;EN;;9;9;9;N;;;;;
00B2;SUPERSCRIPT TWO;No;0;EN;<super> 0032;;2;2;N;SUPERSCRIPT DIGIT TWO;;;;
00B3;SUPERSCRIPT THREE;No;0;EN;<super> 0033;;3;3;N;SUPERSCRIPT DIGIT THREE;;;;
00B9;SUPERSCRIPT ONE;No;0;EN;<super> 0031;;1;1;N;SUPERSCRIPT DIGIT ONE;;;;
ISO 8859-1
Shows ¹,²,³
US-ASCII
Different versions of Windows OS and/or SWI-Prolog
I also uninstalled the 32-bit version and installed the 64-bit version
SWI-Prolog (Multi-threaded, 64 bits, Version 7.2.3 and still the same result.
I also installed the 64-bit version on a different Windows 10 machine that has never had SWI-Prolog on it and still the same result.
I checked an older version SWI-Prolog (Multi-threaded, 64 bits, Version 6.4.1) running on Windows 7 Ultimate Version 6.1.7601, and still the same result.
Other References
SWI-Prolog source code on GitHub
src/os/pl-ctype.c
This module defines:
char_type(?Char, ?Type)
code_type(?Char, ?Type)
Windows-1252
Workaround
Many people are not aware of this as it is still in beta but with Windows 10 64-bit one can run Ubuntu packages and do other Ubuntu things on a Windows subsystem called Bash on Ubuntu on Windows, also know as Windows Subsystem for Linux.
After installing WSL then following the instructions on Installing from PPA (Ubuntu Personal Package Archive) and starting SWI-Prolog, I get the expected output.
findall(C,char_type(C,digit),Cs).
Cs = ['0', '1', '2', '3', '4', '5', '6', '7', '8', '9'].
