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# $EPIC: pattern.txt,v 1.3 2007/05/15 01:28:58 jnelson Exp $

Synopsis:

$pattern(<pattern> <word list>)

Technical:

  • If the <pattern> argument is omitted the empty string is returned.
  • This function returns a space separated word list of all of the words in <word list> that are matched by <pattern>.
  • This is the complement to $filter(), and the inverse of $rpattern().
  • Remember that the words in <word list> are words, so double quoted words are not honored unless you turn xdebug dword on.
  • The <pattern> is also a word, so you should not put double quotes around it unless you have turned xdebug dword on. This is an important difference from epic4.
  • Double quotes around words are not lost if you have xdebug dword turned on. This is an important difference from epic4.
  • There is no reasonable way to support matching a <pattern> that has spaces (a dword) against a word list that does not have spaces (a uword list), since by rule a uword can never contain a space, so it can't match. It has to be all one way or the other.

Practical:

This function lets you “filter” <word list> through a pattern, keeping all of the words that match the pattern and discarding all of the words that do not match the pattern. By appending * to a string and using this function, you can quickly find all words in a word list that start with a particular substring.

Returns:

The list of words from <word list> that are matched by <pattern>.

History:

This function first appeared in “plus-2” (post-ircII, pre-EPIC)

Examples:

$pattern(*oo* foobar blah booya) returns "foobar booya"
$pattern(*a* hello there bob)    returns nothing
$pattern(irc* $myservers())      returns all servers you are connected to
                                 that start with the string "irc".
pattern.txt · Last modified: 2007/05/15 01:28 (external edit)