comment on

What you want is really javascript if you mean do it in the browser. As noted you need a SORTED array of all the possiblities. Then you would do something like:

<head>
<script>
var elements = 6;
options = new Array();
options[0] = 'h';
options[1] = 'he';
options[2] = 'heat';
options[3] = 'hell';
options[4] = 'hello';
options[5] = 'hello world';

function inputDelta() {
    var index = -1;
    var search = someform.search.value;
    if ( search == '' ) {
        someform.guess.value = search;
        return 1;
    }
    var re = new RegExp(search);
    for( i = 0; i < elements; i++ ) {
        if ( options[i] == search ) {
            break;
        }
        if ( options[i].match(re) ) {
            index = i;
        }
    }
    if ( index != -1 ) {
        someform.guess.value = options[index];
    }
    else {
        someform.guess.value = search;
    }   
    return 1;
}
</script>
</head>

<body onLoad="javascript:someform.search.select();someform.search.focu
+s()">
<form name="someform">
<input type="text" name="search" value="Type Search Here"
 onChange="inputDelta()" onKeyup="inputDelta()" onBlur="inputDelta()">
+<br>
<input type="text" name="guess" value="">
</form>
[download]

Note that this is a horrendously inefficient algorithm in that it iterates through a sorted list every time. See File::SortedSeek for a Perl implementation of the binary tree/split the difference algorithm. Have fun implementing it in javascript! If the list of possibilities is large you would put it in a .js file and include it to save the download overhead (if you have repeat access issues)

cheers

tachyon

s&&rsenoyhcatreve&&&s&n.+t&"$'$`$\"$\&"&ee&&y&srve&&d&&print

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	<		`<`
	>		`>`
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