qdapRegex (version 0.7.8)

is.regex: Test Regular Expression Validity

Description

Acts as a logical test of a regular expression's validity. is.regex uses gsub and tests for errors to determine a regular expression's validity. The regular expression must conform to R's regular expression rules (see ?regex for details about how R handles regular expressions).

Usage

is.regex(pattern)

Value

Returns a logical (TRUE is a valid regular expression).

Arguments

pattern

A regular expression to be tested.

See Also

gsub

Examples

is.regex("I|***")
is.regex("I|i")

sapply(regex_usa, is.regex)
sapply(regex_supplement, is.regex) ## `version` is not a valid regex