regex#

Description#

Coerce a string literal to a regular expression. The input regular expression must be a string literal, it cannot be a computed value such as a column value.

The most important use case for this function is where string inputs are available, but regular expression values are not, such as in dashboard parameters.

Return type#

regex

Domain#

This is a scalar function (calculates a single output value for a single input row.)

Categories#

Usage#

regex(string, [ flags ])

Argument

Type

Optional

Repeatable

Restrictions

string

string

no

no

constant

flags

string

yes

no

constant

Examples#

filter match_regex(log, regex($errorExpr))

Given the parameter $errorExpr, turn that into a regular expression and match the column log against it. Syntax errors in the regular expression will be reported at compile time.

The input string should not contain any surrounding slashes; doing so would match against values that contain slash characters.

filter match_regex(log, regex("[0-9]+"))

This matches where a sequence of one or more digits is present in the log string. This is equivalent to the following:

filter match_regex(log, /[0-9]+/)