Pattern Matching Operators

The pattern matching operator, MATCH operator, and its synonym, MATCHES, compare a string expression to a pattern. The syntax for a pattern match expression is:

string MATCH[ES] pattern

The pattern is a general description of the format of the string. It can consist of text or the special characters X, A, and N preceded by an integer used as a repeating factor. X stands for any characters, A stands for any alphabetic characters, and N stands for any numeric characters. For example, 3N is the pattern for character strings made up of three numeric characters. If the repeating factor is zero, any number of characters will match the string. For example, 0A is the pattern for any number of alphabetic characters, including none. If an NLS locale is defined, its associated definitions of alphabetic and numeric determine the pattern matching.

An empty string matches the following patterns: "0A", "0X", "0N", "...", "", '', or \\.

BASIC uses characters rather than bytes to determine string length. In NLS mode, MATCHES works in the same way for multibyte and single-byte character sets.