Beefy Boxes and Bandwidth Generously Provided by pair Networks
Perl: the Markov chain saw
 
PerlMonks  

perlfunc:reverse

by gods
on Aug 24, 1999 at 22:42 UTC ( #244=perlfunc: print w/ replies, xml ) Need Help??

reverse

See the current Perl documentation for reverse.

Here is our local, out-dated (pre-5.6) version:


reverse - flip a string or a list



reverse LIST



In list context, returns a list value consisting of the elements of LIST in the opposite order. In scalar context, concatenates the elements of LIST, and returns a string value consisting of those bytes, but in the opposite order.

    print reverse <>;           # line tac, last line first

    undef $/;                   # for efficiency of <>
    print scalar reverse <>;    # byte tac, last line tsrif

This operator is also handy for inverting a hash, although there are some caveats. If a value is duplicated in the original hash, only one of those can be represented as a key in the inverted hash. Also, this has to unwind one hash and build a whole new one, which may take some time on a large hash.

    %by_name = reverse %by_address;     # Invert the hash

Log In?
Username:
Password:

What's my password?
Create A New User
Chatterbox?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others musing on the Monastery: (8)
As of 2014-07-31 09:06 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    My favorite superfluous repetitious redundant duplicative phrase is:









    Results (248 votes), past polls