Analysis of information sources in references of the Wikipedia article "Regular expression" in English language version.
If the scanner detects a transition on backref, it returns a kind of "semi-success" indicating that the match will have to be verified with a backtracking matcher.
The concept of regular events was introduced by Kleene via the definition of regular expressions.
m/[^abc]/
could also be rendered as /[^abc]/
. The 'm' is only necessary if the user wishes to specify a match operation without using a forward-slash as the regex delimiter. Sometimes it is useful to specify an alternate regex delimiter in order to avoid "delimiter collision". See 'perldoc perlre Archived 2009-12-31 at the Wayback Machine' for more details.Digression: POSIX Submatching
The concept of regular events was introduced by Kleene via the definition of regular expressions.
If the scanner detects a transition on backref, it returns a kind of "semi-success" indicating that the match will have to be verified with a backtracking matcher.
m/[^abc]/
could also be rendered as /[^abc]/
. The 'm' is only necessary if the user wishes to specify a match operation without using a forward-slash as the regex delimiter. Sometimes it is useful to specify an alternate regex delimiter in order to avoid "delimiter collision". See 'perldoc perlre Archived 2009-12-31 at the Wayback Machine' for more details.