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Module:String
Le module String (un mot anglais signifiant chaîne de caractères) permet de manipuler des chaînes de caractères.
Utilisation
Fonctions exportables :
sub
– renvoie une partie de la chaîne de caractères (sub ou sub-string signifie sous-chaîne)trim
– renvoie la chaîne de caractères en supprimant les éventuels espaces au début et/ou à la fin
Autres fonctions :
À compléter…
Modules externes et autres éléments dont ce module a besoin pour fonctionner :
À compléter…
sub
This function returns a substring of the target string at specified indices.
Usage:
{{#invoke:String|sub|target_string|start_index|end_index}}
OR
{{#invoke:String|sub|s=target_string|i=start_index|j=end_index}}
Parameters
- s: The string to return a subset of
- i: The fist index of the substring to return, defaults to 1.
- j: The last index of the string to return, defaults to the last character.
The first character of the string is assigned an index of 1. If either i or j is a negative value, it is interpreted the same as selecting a character by counting from the end of the string. Hence, a value of -1 is the same as selecting the last character of the string.
If the requested indices are out of range for the given string, an error is reported.
match
This function returns a substring from the source string that matches a specified pattern.
Usage:
{{#invoke:String|match|source_string|pattern_string|start_index|match_number|plain_flag|nomatch_output}}
OR
{{#invoke:String|match|s=source_string|pattern=pattern_string|start=start_index |match=match_number|plain=plain_flag|nomatch=nomatch_output}}
Parameters
- s: The string to search
- pattern: The pattern or string to find within the string
- start: The index within the source string to start the search. The first character of the string has index 1. Defaults to 1.
- match: In some cases it may be possible to make multiple matches on a single string. This specifies which match to return, where the first match is match= 1. If a negative number is specified then a match is returned counting from the last match. Hence match = -1 is the same as requesting the last match. Defaults to 1.
- plain: A flag indicating that the pattern should be understood as plain text. Defaults to false.
- nomatch: If no match is found, output the "nomatch" value rather than an error.
If invoked using named parameters, Mediawiki will automatically remove any leading or trailing whitespace from each string. In some circumstances this is desirable, in other cases one may want to preserve the whitespace.
If the match_number or start_index are out of range for the string being queried, then this function generates an error. An error is also generated if no match is found.
For information on constructing Lua patterns, a form of [regular expression], see:
- http://www.lua.org/manual/5.1/manual.html#5.4.1
- http://www.mediawiki.org/wiki/Extension:Scribunto/Lua_reference_manual#Patterns
- http://www.mediawiki.org/wiki/Extension:Scribunto/Lua_reference_manual#Ustring_patterns
find
This function allows one to search for a target string or pattern within another string.
Usage:
{{#invoke:String|find|source_str|target_string|start_index|plain_flag}}
OR
{{#invoke:String|find|source=source_str|target=target_str|start=start_index|plain=plain_flag}}
Parameters
- source: The string to search
- target: The string or pattern to find within source
- start: The index within the source string to start the search, defaults to 1
- plain: Boolean flag indicating that target should be understood as plain text and not as a Lua style regular expression, defaults to true
If invoked using named parameters, Mediawiki will automatically remove any leading or trailing whitespace from the parameter. In some circumstances this is desirable, in other cases one may want to preserve the whitespace.
This function returns the first index >= "start" where "target" can be found within "source". Indices are 1-based. If "target" is not found, then this function returns 0. If either "source" or "target" are missing / empty, this function also returns 0.
This function should be safe for UTF-8 strings.
replace
This function allows one to replace a target string or pattern within another string.
Usage:
{{#invoke:String|replace|source_str|pattern_string|replace_string|replacement_count|plain_flag}}
OR
{{#invoke:String|replace|source=source_string|pattern=pattern_string|replace=replace_string| count=replacement_count|plain=plain_flag}}
Parameters
- source: The string to search
- pattern: The string or pattern to find within source
- replace: The replacement text
- count: The number of occurences to replace, defaults to all.
- plain: Boolean flag indicating that pattern should be understood as plain text and not as a Lua style regular expression, defaults to true
trim
Cette fonction renvoie la chaîne passée en paramètre (non nommé) en supprimant au passage les éventuels espaces et sauts de ligne au début et/ou à la fin de celle-ci.
Utilisation :
{{#invoke:String|trim|texte}}
Paramètres :
- texte : le texte à nettoyer de ses espaces et sauts de ligne au début / à la fin
Exemples
sub
{{#invoke:String|sub|ABCDEFGHIJ|0}} renvoie une erreur, ici l'index commence à 1 (contrairement à d'autres langages de programmation) {{#invoke:String|sub|ABCDEFGHIJ|5}} renvoie EFGHIJ, on commence à partir du 5ème caractère et on prend le reste {{#invoke:String|sub|ABCDEFGHIJ|1|3}} renvoie ABC, on commence à partir du 1er jusqu'au 3ème {{#invoke:String|sub|ABCDEFGHIJ|1|1}} renvoie A {{#invoke:String|sub|ABCDEFGHIJ|-1}} renvoie J, l'index est inversé on commence à la fin {{#invoke:String|sub|ABCDEFGHIJ|-5|-2}} renvoie FGHI {{#invoke:String|sub|ABCDEFGHIJ|-5|2}} renvoie une erreur, l'index de fin doit être après l'index de début (2 est placé avant -5) {{#invoke:String|sub|ABCDEFGHIJ|-5|7}} renvoie FGHI, l'index de fin est bien après l'index de début
trim
###{{#invoke:String|trim|abc}}###
: ###abc######{{#invoke:String|trim| abc}}###
: ###abc######{{#invoke:String|trim|abc }}###
: ###abc######{{#invoke:String|trim| abc }}###
: ###abc###
La documentation de ce module est incluse depuis sa sous-page de documentation (modifier | historique).
Veuillez placer les catégories dans la sous-page /Documentation.
Les éditeurs peuvent travailler dans le bac à sable (créer).
--[[
This module is intended to provide access to basic string functions.
Most of the functions provided here can be invoked with named parameters,
unnamed parameters, or a mixture. If named parameters are used, Mediawiki will
automatically remove any leading or trailing whitespace from the parameter.
Depending on the intended use, it may be advantageous to either preserve or
remove such whitespace.
Unit tests for this module are available at Module:String/tests.
]]
local str = {}
--[[
sub
This function returns a substring of the target string at specified indices.
Usage:
{{#invoke:String|sub|target_string|start_index|end_index}}
OR
{{#invoke:String|sub|s=target_string|i=start_index|j=end_index}}
Parameters
s: The string to return a subset of
i: The fist index of the substring to return, defaults to 1.
j: The last index of the string to return, defaults to the last character.
The first character of the string is assigned an index of 1. If either i or j
is a negative value, it is interpreted the same as selecting a character by
counting from the end of the string. Hence, a value of -1 is the same as
selecting the last character of the string.
If the requested indices are out of range for the given string, an error is
reported.
]]
function str.sub( frame )
local new_args = str._getParameters( frame.args, { 's', 'i', 'j' } );
local s = new_args['s'] or '';
local i = tonumber( new_args['i'] ) or 1;
local j = tonumber( new_args['j'] ) or -1;
local len = mw.ustring.len( s );
-- Convert negatives for range checking
if i < 0 then
i = len + i + 1;
end
if j < 0 then
j = len + j + 1;
end
if i > len or j > len or i < 1 or j < 1 then
return error( 'String subset index out of range' );
end
if j < i then
return error( 'String subset indices out of order' );
end
return mw.ustring.sub( s, i, j )
end
--[[
find
This function allows one to search for a target string or pattern within another
string.
Usage:
{{#invoke:String|find|source_str|target_string|start_index|plain_flag}}
OR
{{#invoke:String|find|source=source_str|target=target_str|start=start_index|plain=plain_flag}}
Parameters
source: The string to search
target: The string or pattern to find within source
start: The index within the source string to start the search, defaults to 1
plain: Boolean flag indicating that target should be understood as plain
text and not as a Lua style regular expression, defaults to true
If invoked using named parameters, Mediawiki will automatically remove any leading or
trailing whitespace from the parameter. In some circumstances this is desirable, in
other cases one may want to preserve the whitespace.
This function returns the first index >= "start" where "target" can be found
within "source". Indices are 1-based. If "target" is not found, then this
function returns 0. If either "source" or "target" are missing / empty, this
function also returns 0.
This function should be safe for UTF-8 strings.
]]
function str.find( frame )
local new_args = str._getParameters( frame.args, {'source', 'target', 'start', 'plain' } );
local source_str = new_args['source'] or '';
local pattern = new_args['target'] or '';
local start_pos = tonumber(new_args['start']) or 1;
local plain = new_args['plain'] or true;
if source_str == '' or pattern == '' then
return 0;
end
plain = str._getBoolean( plain );
local start = mw.ustring.find( source_str, pattern, start_pos, plain )
if start == nil then
start = 0
end
return start
end
--[[
match
This function returns a substring from the source string that matches a
specified pattern.
Usage:
{{#invoke:String|match|source_string|pattern_string|start_index|match_number|plain_flag|nomatch_output}}
OR
{{#invoke:String|pos|s=source_string|pattern=pattern_string|start=start_index
|match=match_number|plain=plain_flag|nomatch=nomatch_output}}
Parameters
s: The string to search
pattern: The pattern or string to find within the string
start: The index within the source string to start the search. The first
character of the string has index 1. Defaults to 1.
match: In some cases it may be possible to make multiple matches on a single
string. This specifies which match to return, where the first match is
match= 1. If a negative number is specified then a match is returned
counting from the last match. Hence match = -1 is the same as requesting
the last match. Defaults to 1.
plain: A flag indicating that the pattern should be understood as plain
text. Defaults to false.
nomatch: If no match is found, output the "nomatch" value rather than an error.
If invoked using named parameters, Mediawiki will automatically remove any leading or
trailing whitespace from each string. In some circumstances this is desirable, in
other cases one may want to preserve the whitespace.
If the match_number or start_index are out of range for the string being queried, then
this function generates an error. An error is also generated if no match is found.
For information on constructing Lua patterns, a form of [regular expression], see:
* http://www.lua.org/manual/5.1/manual.html#5.4.1
* http://www.mediawiki.org/wiki/Extension:Scribunto/Lua_reference_manual#Patterns
* http://www.mediawiki.org/wiki/Extension:Scribunto/Lua_reference_manual#Ustring_patterns
]]
function str.match( frame )
local new_args = str._getParameters( frame.args, {'s', 'pattern', 'start', 'match', 'plain', 'nomatch'} );
local s = new_args['s'] or '';
local start = tonumber( new_args['start'] ) or 1;
local plain_flag = str._getBoolean( new_args['plain'] or false );
local pattern = new_args['pattern'] or '';
local match_index = math.floor( tonumber(new_args['match']) or 1 );
local nomatch = new_args['nomatch'];
if s == '' then
return error( 'Target string is empty' );
end
if pattern == '' then
return error( 'Pattern string is empty' );
end
if math.abs(start) < 1 or math.abs(start) > mw.ustring.len( s ) then
return error( 'Requested start is out of range' );
end
if match_index == 0 then
return error( 'Match index is out of range' );
end
if plain_flag then
pattern = str._escapePattern( pattern );
end
local result
if match_index == 1 then
-- Find first match is simple case
result = mw.ustring.match( s, pattern, start )
else
if start > 1 then
s = mw.ustring.sub( s, start );
end
local iterator = mw.ustring.gmatch(s, pattern);
if match_index > 0 then
-- Forward search
for w in iterator do
match_index = match_index - 1;
if match_index == 0 then
result = w;
break;
end
end
else
-- Reverse search
local result_table = {};
local count = 1;
for w in iterator do
result_table[count] = w;
count = count + 1;
end
result = result_table[ count + match_index ];
end
end
if result == nil then
if nomatch == nil then
return error( 'Match not found' );
else
return nomatch;
end
else
return result;
end
end
--[[
replace
This function allows one to replace a target string or pattern within another
string.
Usage:
{{#invoke:String|replace|source_str|pattern_string|replace_string|replacement_count|plain_flag}}
OR
{{#invoke:String|replace|source=source_string|pattern=pattern_string|replace=replace_string|
count=replacement_count|plain=plain_flag}}
Parameters
source: The string to search
pattern: The string or pattern to find within source
replace: The replacement text
count: The number of occurences to replace, defaults to all.
plain: Boolean flag indicating that pattern should be understood as plain
text and not as a Lua style regular expression, defaults to true
]]
function str.replace( frame )
local new_args = str._getParameters( frame.args, {'source', 'pattern', 'replace', 'count', 'plain' } );
local source_str = new_args['source'] or '';
local pattern = new_args['pattern'] or '';
local replace = new_args['replace'] or '';
local count = tonumber( new_args['count'] );
local plain = new_args['plain'] or true;
if source_str == '' or pattern == '' then
return source_str;
end
plain = str._getBoolean( plain );
if plain then
pattern = str._escapePattern( pattern );
replace = mw.ustring.gsub( replace, "%%", "%%%%" ); --Only need to escape replacement sequences.
end
local result;
if count ~= nil then
result = mw.ustring.gsub( source_str, pattern, replace, count );
else
result = mw.ustring.gsub( source_str, pattern, replace );
end
return result;
end
--[[
trim
Cette fonction retourne son unique paramètre en supprimant les espaces
et sauts de ligne au début et à la fin (fonction "trim")
Usage :
{{#invoke:String|trim|string}}
Paramètres :
la chaîne 'string' dont on veut supprimer les éventuels espaces
et sauts de ligne au début et/ou à la fin
]]
function str.trim(frame)
local txt = frame.args[1]
if not txt or txt == "" then
return ""
end
-- on retourne txt en le "stripant"
return mw.text.trim(txt)
end
--[[
Helper function that populates the argument list given that user may need to use a mix of
named and unnamed parameters. This is relevant because named parameters are not
identical to unnamed parameters due to string trimming, and when dealing with strings
we sometimes want to either preserve or remove that whitespace depending on the application.
]]
function str._getParameters( frame_args, arg_list )
local new_args = {};
local index = 1;
local value;
for i,arg in ipairs( arg_list ) do
value = frame_args[arg]
if value == nil then
value = frame_args[index];
index = index + 1;
end
new_args[arg] = value;
end
return new_args;
end
--[[
Helper Function to interpret boolean strings
]]
function str._getBoolean( boolean_str )
local boolean_value;
if type( boolean_str ) == 'string' then
boolean_str = boolean_str:lower();
if boolean_str == 'false' or boolean_str == 'no' or boolean_str == '0'
or boolean_str == '' then
boolean_value = false;
else
boolean_value = true;
end
elseif type( boolean_str ) == 'boolean' then
boolean_value = boolean_str;
else
error( 'No boolean value found' );
end
return boolean_value
end
--[[
Helper function that escapes all pattern characters so that they will be treated
as plain text.
]]
function str._escapePattern( pattern_str )
return mw.ustring.gsub( pattern_str, "([%(%)%.%%%+%-%*%?%[%^%$%]])", "%%%1" );
end
return str