Wikipedia Regular Expressions

Line Breaks

SEARCH
	for legal and illegal forms of HTML Line Break Tag. Open tag, closing tag, self-closing tag. Allow whitespace before and after 'br' Tag ID. Allow whitespace before opening Tag Delimiter (<) and after closing Tag Delimiter (>).

Wikimedia Tag Parser has funny rules for an HTML Line Break Tag. No matching Begin/End tags (<br></br>). Either Begin or End tag alone counts as a Line Break Tag. After normal start to tag (<br or </br), almost anything goes until closing '>'. Including a text Line Break!

	\s*<\/?br(\s*[^|{}]*)?>\s*

REPLACE
	HTML Line Break Tag with Wikimedia {{break}} template. Replacement string includes a space before opening Template Delimiter ({{) and after closing Template Delimiter (}}).

	{{break | 1}}

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Spacing for Pipe Bars (|) in Templates

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    for Pipe Bars (|), possibly preceded or followed by whitespace. Do not accept a newline character (NL) as whitespace. In practice, accept non-NL whitespace preceding or following a Pipe Bar. In aspiration, reject any string of whitespace that has an NL in it. But it was a lot of work to get the search expression to work as well as it does. Improving the search expression is a task for somewhere between later and never.

REPLACE
    existent or nonexistent whitespace with nice whitespace