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qdapRegex (version 0.3.2)

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)

Arguments

pattern
A regular expression to be tested.

Value

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

See Also

gsub

Examples

Run this code
is.regex("I|***")
is.regex("I|i")

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

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