perlfunc
gods
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reverse - flip a string or a list
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reverse
<FONT SIZE=-1>LIST</FONT>
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In list context, returns a list value consisting of the elements of
<FONT SIZE=-1>LIST</FONT> in the opposite order. In scalar context, concatenates the elements of
<FONT SIZE=-1>LIST,</FONT> and returns a string value consisting of those bytes, but in the opposite order.
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<PRE> print reverse <>; # line tac, last line first
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<PRE> undef $/; # for efficiency of <>
print scalar reverse <>; # byte tac, last line tsrif
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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.
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<PRE> %by_name = reverse %by_address; # Invert the hash
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