Module:Ustring
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This module directly imports all functions from the mw.ustring library. Documentation for each function can be found there.
The module takes an indefinite number of arguments. Arguments given as |s1=, |s2=, etc, are read first, and are used as strings. All remaining numerical arguments are coerced to number type if possible, and remain strings if not. If you wish for a numerical (i.e. unnamed or "|1=", "|2=") to remain a string, you can simply escape it by inserting \ at the beginning of the string.
Note that MediaWiki will always trim whitespace from named arguments; to give arguments with surrounding whitespace you must use unnamed parameters starting with \.
| To pass this... | Write this | Explanation |
|---|---|---|
" 0123 " |
|\ 123 |
To get surrounding whitespace must use unnamed, but must precede with \ to indicate that it isn't a number.
|
"0123" |
|s1=0123 |
If you don't need to preserve whitespace use |s1= etc.
|
"0123" |
|1=\0123 |
If you don't need to preserve whitespace explicitly use |1= etc.
|
In another template, to pass its parameter {{{1}}}, preserving whitespace |
|\{{{1}}} |
Must provide the \ with unknown string input.
|
In another template, to pass its parameter {{{1}}}, stripping whitespace |
|s1={{{1}}} |
|
In another template, to pass its parameter {{{1}}}, stripping whitespace |
|1=\{{#if:1|{{{1}}}}} |
You can also wrap results in tags. All other unused arguments will be passed to
frame:extensionTag
Usage
[edit]{{#invoke:Ustring|function_name|arg1|arg2|...}} is equivalent to mw.ustring.function_name
( arg1, arg2, ... )
Example using mw.ustring.sub
[edit]{{#invoke:Ustring|sub|s1=abcde|2|4}}
produces:
bcd
Example using mw.ustring.gsub
[edit]{{#invoke:Ustring|gsub|s1=1234|23|}}
produces:
14
Example using mw.ustring.char
[edit]&#{{#invoke:ustring|char|49|48|59}}
produces:
Example using mw.ustring.match
[edit]{{#invoke:Ustring|match|s1=abcde|s2=(c%w)}}
produces:
cd
Note: Only the first match is returned. Additional returns are omitted because mw.ustring.gsub's second return value is generally undesirable.
Example using mw.ustring.len
[edit]{{#invoke:Ustring|len|a string of twenty-nine chars}}
produces:
29
Example using tag arguments
[edit]{{#invoke:Ustring|match
|s1={{Module:Ustring}}|%s%s%sif%snot%s[^%s]+%sthen.+%
<!--enter an actual newline character to match '\n'-->%s%s%send
|tag=syntaxhighlight|lang=lua}}
produces:
if not fargs.tag then
return (what(unpack(args))) -- Outside parens truncate to first result avoiding tail call
end
local tagargs = {}
for x, y in pairs(fargs) do
if not fargsused[x] then tagargs[x] = y end
end
Note that:
<syntaxhighlight lang="lua">{{#invoke:Ustring|match
|s1={{Module:Ustring}}|%s%s%sif%snot%s[^%s]+%sthen.+%
<!--enter an actual newline character to match '\n'-->%s%s%send}}</syntaxhighlight>
produces:
{{#invoke:Ustring|match
|s1={{Module:Ustring}}|%s%s%sif%snot%s[^%s]+%sthen.+%
<!--enter an actual newline character to match '\n'-->%s%s%send}}
Errors
[edit]Errors from accessing mw.ustring should be maintained, e.g.:
{{#invoke:Ustring|xyzzy}}
should produce:
Script error: The function "xyzzy" does not exist.
and
{{#invoke:Ustring|maxPatternLength}}
should produce:
Script error: "maxPatternLength" is not a function.
See also
[edit]
require('strict')
return setmetatable({}, {
__index = function(t, k)
local what = mw.ustring[k]
if type(what) ~= "function" then
return what
end
return function(frame)
local fargs = frame.args
local fargsused = { tag = true }
local args = {}
local str_i = 1
while fargs['s' .. str_i] do
fargsused['s' .. str_i] = true
args[str_i] = fargs['s' .. str_i]
str_i = str_i + 1
end
for i, v in ipairs(fargs) do
fargsused[i] = true
args[i + str_i - 1] = tonumber(v) or v:gsub("^\\", "", 1)
end
if not fargs.tag then
return (what(unpack(args))) -- Outside parens truncate to first result avoiding tail call
end
local tagargs = {}
for x, y in pairs(fargs) do
if not fargsused[x] then tagargs[x] = y end
end
return frame:extensionTag{name = fargs.tag, content = what(unpack(args)), args = tagargs}
end
end
})