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wordtoindex [2006/08/29 16:08] (current)
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 +# $EPIC: wordtoindex.txt,​v 1.2 2006/08/20 18:32:13 sthalik Exp $
 +======Synopsis:​======
 +$__wordtoindex__(<​number>​ <​list>​)
 +
 +======Technical:​======
 +   * If the <​number>​ argument is omitted, the empty string is returned.
 +   * If <​number>​ is negative, then the value 0 is returned.
 +   * If <​number>​ is greater than the actual number of words in <​list>,​ then the return value of this function is the same as would be returned by $strlen(<​list>​).
 +   * There is only one space that separates <​number>​ from <​list>​. ​ Any further spaces between <​number>​ and <​list>​ are part of <​list>​ for the purpose of counting.
 +   * The return value is the character position (as would be returned by $[[index]]() and could be used by $[[right]]() et al) of the first character in the <​number>​th word in <​list>​.
 +   * <​number>​ counts from zero!
 +
 +======Practical:​======
 +The most practical use of this function is to permit you to find the 
 +beginning position of a word in a string, especially after you have had
 +to change the length of some of the words in the list.  This technique is
 +most obviously used by tab completion scripts which will take the input 
 +line ($L), the cursor position ($[[curpos]]()),​ and use the $[[indextoword]]() ​
 +function to figure out where the cursor is.  Then they rewrite the input
 +line using tab completion, and use $wordtoindex() to figure out where the
 +cursor is supposed to go after the input line has been rewritten.
 +
 +======Returns:​======
 +The number of characters before the beginning of the <​number>​th word
 +in <​list>,​ where <​number>​ counts from zero.
 +
 +======Examples:​======
 +<​file>​
 +$wordtoindex(2 foo bar blah)           ​returns 8
 +$wordtoindex(999 foo bar blah)         ​returns 12
 +$wordtoindex(-1 foo bar blah)          returns 0
 +</​file>​
  
wordtoindex.txt ยท Last modified: 2006/08/29 16:08 (external edit)