posnq (position, no quotes) returns the numerical start position of the first occurrence of one piece of text ("target") inside another ("source"). UTC characters are supported.
It returns nil by default if no match is found, or if either parameter is blank. If no match is found it can return the value of an optional "nomatch" parameter.
It takes the text to be searched in as the first unnamed parameter (or |source=), which is trimmed.
It takes the text to match as the second unnamed parameter (or |target=), which is trimmed and any double quotes " are stripped out. That allows spaces at the beginning or end of the match string to be included in a consistent manner.
It can take an optional third unnamed parameter (or |plain=), which is trimmed. If it's set to false, then the search accepts Lua pattern-matching for the target, otherwise a plain search is used.
It can take an optional fourth unnamed parameter (or |nomatch=), which is trimmed. This value is returned if no match occurs. Setting |nomatch=0 makes the output compatible with the find function in Module:String.
