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in reply to dir match, dir may or may not appear

In your regex [^/]+{0,1} does not make sense if I understand it correctly, basically you say
anything but a slash, at least one time, then you say at least 0 time at most 1... you gotta choose which you want, either it is

[^/]+ or [^/]? (equivalent to {0,1}) For what you want to do I'd say: m#\A/usr/([^/]+/)?bin#

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Re^2: dir match, dir may or may not appear
by hellosarathy (Novice) on Jan 12, 2016 at 10:18 UTC
    Thanks,

    I meant "(slash followed by anything except slash) to occur 0 or 1 time"

    Basically 0 or 1 dir can appear inbetween /usr and bin/

      The "?" quantifier means to match 0 or 1 times as specified in the "Quantifiers" section of perlre. Therefore your pattern to match this could be simply (/[^/]+)? which is similar to QuillMeantTen's approach above.