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Pattern matching

A pattern is a string which may contain the following special characters:

* Matches any sequence of characters in string, including a null string.
? Matches any single character in string.
! if the pattern is starting with this character then the pattern match will be case-sensitive. In this case the starting character is excluded from the match.
( This position within the pattern is matching the start of a word, either beginning with a letter or a digit.
) This position within the pattern is matching the end of a word, either ending with a letter or a digit.
\x Matches the single character x. This provides a way of avoiding the special interpretation of the characters ()*!?\ in pattern. Also the blank character will be protected from a special interpretation.

Pattern matching is in general case-insensitive, except if the pattern is starting with the special character !.

Also the blank character will be interpreted as a special character (if not protected), it is matching any number of blank characters, but not the empty string. But if a separating character (e.g. a comma) is adjacent to a blank character, also an empty string will match. In this way mistakes in spelling can be compensated. A protected blank character (preceded by a backslash) will match exactly one blank character.

Furthermore the following special rule applies: a parenthetical expression – e.g. "(J*)" – will not match any string which contains blanks or separating characters.

Examples

Polgar, J*

This pattern can match the following strings: "Polgar, J", and "Polgar, Judit".

A?erba?h

This can match the following names: "Averbakh" (English spelling), and "Awerbach" (German spelling).

Kasparov*

This can match, among others, the following strings: "Kasparov", "Kasparova", "Kasparov, Gary", and "Kasparova, Tatiana".

Kasparov*)

This can match the same strings as in the latter case, because all these strings are ending with a letter. But a string like "Kasparov, G." cannot match.

(Kasparov*)

This can match, among others, the strings "Kasparov", and "Kasparova", but it cannot match "Kasparov, Gary", or "Kasparova, Tatiana". A parenthetical expression is excluding the match of blanks and separating characters.

(Kasparov)*

This can match, among others, the strings "Kasparov", and "Kasparov, Gary", but it cannot match "Kasparova", or "Kasparova, Tatiana".

Kasparov*,*

This can match, among others, the strings "Kasparov, Gary", and "Kasparova, Tatiana", but it cannot match "Kasparov", or "Kasparova".

Kasparov, Gary

This is matching the string "Kasparov, Gary". Because of the special rule with separating characters also the following strings will match: "Kasparov,Gary" (lacking blank character), and "Kasparov,  Gary" (one blank too many).

Kasparov,\ Gary

This is only matching the string "Kasparov, Gary" (exactly one blank character).

!MacDonald

This is matching "MacDonald", but not "Macdonald", because the match is case-sensitive.

*\(Berlin\)

This can match the string "Germany (Berlin)", among others. The characters (, and ) do not have any special meaning, because they are protected by a backslash. This means that the string "Germany Berlin" cannot match.