examples/regex/regex.html
<script>
var text = 'There is a number 42 in this an another number #123 but nothing else.';
console.log(text);

var pattern = /\d+/;
var match = pattern.exec(text);
if (match) {
    console.log(match[0]);
}

var m = /\d+/.exec(text);
if (m) {
    console.log(m[0]);
}
</script>