In addition to normal arithmetic and logical operators, AWK expressions include the tilde operator, codice_6, which matches a regular expression against a string. As handy syntactic sugar, "/regexp/" without using the tilde operator matches against the current record; this syntax derives from sed, which in turn inherited it from the ed editor, where codice_7 is used for searching. This syntax of using slashes as delimiters for regular expressions was subsequently adopted by Perl and ECMAScript, and is now common. The tilde operator was also adopted by Perl.