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indextoitem [2006/08/01 03:45] (current) – created - external edit 127.0.0.1
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 +# $EPIC: indextoitem.txt,v 1.2 2006/08/01 03:40:36 sthalik Exp $
 +======Synopsis:======
 +$indextoitem(<array> <index number>)
 +$itemtoindex(<array> <item number>)
 +
 +======Technical:======
 +These functions are used to convert between array item numbers are index
 +numbers.
 +
 +Item numbers are counted incrementally as items are added to an array,
 +starting at 0 (zero).  Each new item uses the next available item number;
 +if there are 5 items in an array, the next item that may be added is item
 +number 5 (remember that we count from zero... 5 items is 0..4).
 +
 +Index numbers represent each items position in the array when sorted.
 +Items are sorted based on their ascii values.  This is generally
 +alphabetical; however, since it is based on ascii values, all capital
 +letters are sorted after all lowercase letters.  It follows a sorting
 +algorithm similar to the $[[sort]]() function's.
 +
 +======Practical:======
 +The $__indextoitem__() function converts an index number in the given array
 +to its corresponding item number; $__itemtoindex__() does just the opposite.
 +This is mostly useful in conjunction with $[[igetitem]]() or $[[ifinditem]](),
 +allowing an array to be dealt with in a logical order.
 +
 +======Returns:======
 +<file>
 +  -2   cannot find index/item number in array
 +  -1   cannot find named array
 +> -1   item number corresponding to given index number (and vice verse)
 +</file>
 +
 +======Examples:======
 +<file>
 +$setitem(booya 0 hello)
 +$setitem(booya 1 goodbye)
 +$itemtoindex(booya 0)                 returns 1
 +$indextoitem(booya 1)                 returns 0
 +$itemtoindex(foobar 0)                returns -1
 +$itemtoindex(booya 100)               returns -2
 +</file>
  
indextoitem.txt · Last modified: 2006/08/01 03:45 by 127.0.0.1