If you want a markup to produce something that is interpreted by wiki be careful. E.g. if I you want a style, I start by coding

• Markup('{red}', '_begin', '/{red}/', '>>red<<');

However, PmWiki will show the text >>red<< instead of interpreting the style and changing the color. This is because the markup handling styles looks for << .... >> . Thus, what I need is

• Markup('{red}', '_begin', '/{red}/', '<<red>>');

To make sure the ouput of a markup is understood, one better reads the definition of the consumer, in this case in stdmarkup.php.

parallel use of the " <br> " symbol, to break lines

If you want to use the " <br> " symbol, to break lines,
like in .html pages
(parallel to the " \\ " symbol),
put the following in your config.php file:

## using <br> , to break lines.
##
## optional, if you may have <br clear='all'>
## Markup('<br clear=all>','inline','/&lt;br\\s+clear=([\'"]?)all\\1\\s*\\/?&gt;/i',"<br clear='all' />");
##
## One thing to know is that the symbols "<" and ">" are encoded in the page 
## source text as "&lt;" and "&gt;" and in custom markup the encoded ones should 
## be used.
##
Markup('<br>','inline','/&lt;br\\s*\\/?&gt;/i',"<br />");