# $EPIC: indextoword.txt,v 1.3 2006/08/01 03:47:40 sthalik Exp $
======Synopsis:======
$__indextoword__(<position> <text>)

======Technical:======
   * If the <position> argument is omitted the empty string is returned.
   * If the <position> argument is a negative number the empty string is returned.
   * If the <text> argument is omitted the empty string is returned.
   * If the length of <text> is less than <position> the empty string is returned.
   * Otherwise, the return value returns a value suitable for use with the $word() function (or other word functions) representing the word that contains the <position>th character which should be a value returned by $index() or the like.
   * Remember that <position> counts from zero!
   * Remember that the return value counts from zero!

======Practical:======
The most obvious application of this function is to find the word on the
input line underneath the cursor.  $L is the contents of the input line 
and $curpos() tells you where the cursor is; you can then use something
like this:

  $word($indextoword($curpos() $L) $L)

to extract the word "underneath" the cursor.  This is the fundamental
mechanics of how tab completion scripts know what to complete.

======Returns:======
A number suitable for use with the word manipulation functions that
represents the word that contains the <position>th character in <text>.
Both <position> and the return value count from zero.

======Examples:======
<file>
$word($indextoword($curpos() $L) $L)   returns the word under the cursor
@ foo = [one two. three.]
$indextoword($index(. $foo) $foo)      returns 1 (the . in ``two.'')
$indextoword($rindex(. $foo) $foo)     returns 2 (the . in ``three.'')
$indextoword(100 testing)              returns the empty string
</file>