Ready for use This module is rated as ready for general use. It has reached a mature form and is thought to be relatively bug-free and ready for use wherever appropriate. It is ready to mention on help pages and other Wikipedia resources as an option for new users to learn. To reduce server load and bad output, it should be improved by sandbox testing rather than repeated trial-and-error editing.

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 \.

How to pass inconvenient strings
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

[kulemba source]

((#invoke:Ustring|function_name|arg1|arg2|...)) is equivalent to mw.ustring.function_name( arg1, arg2, ... )

Example using mw.ustring.sub

[kulemba source]

((#invoke:Ustring|sub|s1=abcde|2|4))

produces:

bcd

Example using mw.ustring.gsub

[kulemba source]

((#invoke:Ustring|gsub|s1=1234|23|))

produces:

14

Example using mw.ustring.char

[kulemba source]

&#((#invoke:ustring|char|49|48|59))

produces:




Example using mw.ustring.match

[kulemba source]

((#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 tag arguments

[kulemba source]
((#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

[kulemba source]

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

[kulemba source]
String-handling templates (help page)
Substring (select chunk of string by its position)
((str sub new)) Select a substring based on starting and ending index counted in either direction.
((str left)) Keep the first N characters of a string, or duplicate it to N characters.
((str crop)) Return all but the last N characters of a string.
((str index)) Return the N-th character of a string.
((str right)) Return substring starting at N-th character to end of string.
((str rightc)) Return the last N characters of a string; or a given value if empty.
((str sub old)) Return substring of given length starting at N-th character.
Trimming (select/remove chunk of string by character type)
((trim)) Trim any leading or trailing whitespace
((str letter/trim)) Trim down to the beginning letters.
((str number/trim)) Trim down to the beginning numbers.
((trim brackets)) Trim any leading or trailing square brackets.
((trim quotes)) Trim leading or trailing matching quotes.
((trim leading)) Trim up to six instances of specified <prefix>.
((string split)) Extract a short string from a long string.
((first word)) Trim down to the first space.
((remove first word)) Remove anything before the first space.
((last word)) Trim down from the last space.
((remove last word)) Remove anything after the last space.
Select/remove specific item from string
((delink)), ((trim brackets)) Removes wikilink brackets (wikicode); all or outer only.
((Plain text)) Removes wikicode (formatting and brackets)
((PAGENAMEBASE)) Trim off any parenthesis text at the end of a string (disambiguation).
((title disambig text)) Returns text in parentheses at the end of a string (disambiguation).
((WikiProjectbasename)) Removes "WikiProject" from a pagename.
((ship prefix)) Returns the length of a ship's name prefix, if listed (ship names).
((title year)) Returns the 3-or-4-digit year from a pagename, if any.
((title decade)) Returns the 4-digit decade (e.g. "1740s") from a pagename, if any.
((title number)) Returns any number from a pagename.
Insertion, replacement and length
((loop)) Repeat character string a specified number of times.
((replace)) Returns the string, after replacing all occurrences of a specified string with another string.
((str rep)) Returns the string, after replacing the first occurrence of a specified string with another string.
((digits)) Returns the string, after removing all characters that are not digits 0–9
((Nowiki)) Displays wikitext as plain text.
((str len)) Returns a string's length.
((str ≥ len)) Check if a string is "longer or equally long" or "shorter" than a given length.
((str ≤ len)) Check if a string is "shorter or equally long" or "longer" than a given length.
((str ≠ len)) Check if a string is "not equal" or "equal" to a given length.
Analysis and searching
((str startswith))
((str endswith))		 Check if a string starts or ends with a given string.
((str find)), ((strfind short)) Returns the numerical location of a given string in a string.
((in string)) Returns optional string when given string is not found
((str count)) Count the number of occurrences of a pattern within a string.
((a or an)) Takes a noun and produces the appropriate indefinite article, based on whether the first letter is a vowel.
((Array)) Array manipulation and retrieval.
((Isnumeric)) Returns number when true, blank when not numeric.
((str letter)) Returns the number of letters that begin a string.
((str number)) Returns the number of numbers that begin a string.
Modules and built-in functions
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
})
Mitundu