When a reluctant (or lazy) quantifier is followed by a pattern that can match the empty string or directly by the end of the regex, it will always
match zero times for *?
or one time for +?
. If a reluctant quantifier is followed directly by the end anchor
($
), it behaves indistinguishably from a greedy quantifier while being less efficient.
This is likely a sign that the regex does not work as intended.
Noncompliant code example
str.split(/.*?x?/); // Noncompliant, this will behave just like "x?"
/^.*?$/.test(str); // Noncompliant, replace with ".*"
Compliant solution
str.split(/.*?x/);
/^.*$/.test(str);