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prefix [2006/08/29 16:08] (current)
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 +# $EPIC: prefix.txt,v 1.4 2006/08/19 04:05:34 sthalik Exp $
 +======Synopsis:======
 +$__prefix__(<word list>)
 +
 +======Technical:======
 +   * If the <word list> argument is omitted the empty string is returned.
 +   * The return value of this function is whatever string is the common initial substring (CIS) of all of the words in <word list> If there is no CIS in <word list>, the empty string is returned.
 +   * This function uses an O(M*N) algorithm where M is the number of words in <word list> and N is the length of the first word in <word list>. Take this into consideration when planning.
 +
 +======Practical:======
 +This function can be used to do pseudo-completion.  To explain,
 +consider if you are working on a tab completion script and the user 
 +types "foo" and presses tab.  Normally you would extract from $[[onchannel]]()
 +everything that matched "foo*", but what if that returns more than one
 +word?  It is considerate to the user to complete as much as possible for
 +them and then prompt them for the rest.  So let's say that you had two
 +users, "foobar" and "foobaz" When the user pressed <tab> after typing
 +"foo" you would do something like this:
 +
 +<file>
 +# Some code goes here to put "foo" in $input.
 +@ users = filter($input* $onchannel())
 +@ result = prefix($users)
 +if (numwords($users) > 1) { beep }
 +# Some code goes here to remove the 'foo' from the input
 +#   line and paste $result in its place.
 +</file>
 +
 +$result will contain "fooba" because "fooba" is the CIS of the word 
 +list (foobar foobaz).  So when the user presses <tab> you will put the
 +string "fooba" in place of "foo" and beep to let them know that it is
 +not an exact match.  You could use $users to tell them what their options
 +are, if you wanted to.
 +
 +If the user typed something like "boo" and there were no users on the 
 +channel whose nickname started with "boo", then $result would be the
 +empty string.  You could trap that as well and give the user an error
 +message.
 +
 +======Returns:======
 +The Common Initial Substring (CIS) of all of the words in <word list>
 +
 +======Examples:======
 +<file>
 +$prefix(foobar foobaz foobooya)      returns "foob"
 +$prefix(one two three)               returns the empty string.
 +</file>
  
prefix.txt ยท Last modified: 2006/08/29 16:08 (external edit)