Sebutkan definisi regular expression?

In programming, a regular expression is an expression that explains a pattern for a string. A string matches a regular expression if that string follows the pattern of that regular expression. For...

A Perl regular expression that is meant to check if a string has only letters, underscores, hyphens, and numbers would look something like this: /^[A-Za-z0-9_-]+/$ However, regular expressions...

Use the preg functions (ereg functions are deprecated) Wiki regex to form your regex string

echo or print < both of which write text: <?php echo "TEXT"; print "TEXT"; ?>

word boundary '/b' is any character other than alphanumeric and underscore ie. [^A-Za-z0-9_]