View source for Module:Ustring/doc

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This module directly imports all functions from the {{luaref|Ustring library|mw.ustring}} library. Documentation for each function can be found there.

The module takes an indefinite number of arguments. All arguments are coerced as number type if possible. If you wish for something to remain a string, you can simply escape it by insert <code>\</code> at the beginning of the string.

You can also wrap results in tags. All non-number indexed arguments will be passed to {{luaref|frame:extensionTag}}

== Usage ==

<code><nowiki>{{</nowiki>#invoke:{{BASEPAGENAME}}|''function_name''|arg1|arg2|...}}</code> is equivalent to {{luaref|Ustring library|mw.ustring.''function_name''|args=arg1, arg2, ...}}

===Example using mw.ustring.sub===
<code><nowiki>{{#invoke:Ustring|sub|abcde|2|4}}</nowiki></code>

produces:

{{#invoke:Ustring|sub|abcde|2|4}}

===Example using mw.ustring.gsub===
<code><nowiki>{{#invoke:Ustring|gsub|1234|23|}}</nowiki></code>

produces:

{{#invoke:Ustring|gsub|1234|23|}}

===Example using mw.ustring.char===
<code><nowiki>&amp;amp;#{{#invoke:ustring|char|49|48|59}}</nowiki></code>

produces:

&amp;#{{#invoke:ustring|char|49|48|59}}

This is nice for escaping character sequences in other modules; for example:
<syntaxhighlight lang="lua">
p = {}
function p.main(frame)
  local str = '1-2-2{{#invoke:ustring|char|45}}1-3'
  return frame:preprocess(str:gsub('-', '/'))-- == '1/2/2-1/3'
end
return p
</syntaxhighlight>

===Example using mw.ustring.match===
<code><nowiki>{{#invoke:Ustring|match|abcde|(c%w)}}</nowiki></code>

produces:

{{#invoke:Ustring|match|abcde|(c%w)}}

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===
<pre>{{#invoke:Ustring|match
|{{Module:Ustring}}|%s%s%sif%snot%s[^%s]+%sthen.+%
<!--enter an actual newline character to match '\n'-->%s%s%send
|tag=syntaxhighlight|lang=lua}}</pre>
produces:
{{#invoke:Ustring|match
|{{Module:Ustring}}|%s%s%sif%snot%s[^%s]+%sthen.+%
<!--enter an actual newline character to match '\n'-->%s%s%send
|tag=syntaxhighlight|lang=lua}}

Note that:
{{#tag:pre|<nowiki><syntaxhighlight lang="lua">{{#invoke:Ustring|match
|{{Module:Ustring}}|%s%s%sif%snot%s[^%s]+%sthen.+%
<!--enter an actual newline character to match '\n'-->%s%s%send}}</syntaxhighlight></nowiki>}}
produces:
<syntaxhighlight lang="lua">{{#invoke:Ustring|match
|{{Module:Ustring}}|%s%s%sif%snot%s[^%s]+%sthen.+%
<!--enter an actual newline character to match '\n'-->%s%s%send}}</syntaxhighlight>

== Errors ==
Errors from accessing {{luaref|Ustring library|mw.ustring}} should be maintained, e.g.:

<code><nowiki>{{#invoke:Ustring|xyzzy}}</nowiki></code>

should produce:

{{script error|Script error: The function "xyzzy" does not exist.}}

and

<code><nowiki>{{#invoke:Ustring|maxPatternLength}}</nowiki></code>

should produce:

{{script error|Script error: "maxPatternLength" is not a function.}}

== See also ==
* [[Module:String]]
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