XQuery

Using Flags

Three XQuery functions use regular expressions: matches, replace, and tokenize. Each of these functions accepts a $flags argument that allows for additional options in the interpretation of the regular expression, such as multi-line processing and case insensitivity. Options are indicated by single letters; the $flags argument is a string that can include any of the valid letters in any order, and duplicates are allowed.

The $flags argument allows four options:

s

The letter s indicates dot-all mode, which affects the period wildcard (.). (This is known as single-line mode in Perl.) This means that the period wildcard matches any character whatsoever, including the line feed (#xA) character. If the letter s is not specified, the period wildcard matches any character except the line feed (#xA) character.

m

The letter m indicates multi-line mode, which affects anchors. In multi-line mode, the ^ and $ characters match the beginning and end of a line, as well as the beginning and end of the whole string.

i

The letter i indicates case-insensitive mode. This means that matching does not distinguish between normal characters that are case variants of each other, as defined by Unicode. For example, in case-insensitive mode, [a-z] matches the lowercase letters a through z, uppercase letters A through Z, and a few other characters such as a Kelvin sign. The meaning of category escapes such as \p{Lu} is not affected.

x

The letter x indicates that whitespace characters ...