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NAME

Hub::Perl::Compare - Scalar value comparisons

SYNOPSIS

  # usage: this_script.pl operator val1 val2
  use Hub qw(:standard);
  print compare(@ARGV) ? "True\n" : "False\n";

DESCRIPTION

Efficient routine to compare scalar values when the operator is variable.

PUBLIC METHODS

compare

Wrapper for Perl's internal comparison operators.
 Usage: compare $operator, $left_operand, $right_operand

Support runtime comparison when the operator is held as a scalar.

Where $operator may be one of:

  eq        Equal
  ne        Not equal
  lt        Less than
  le        Less than or equal
  gt        Greater than
  ge        Greater than or equal
  ==        Numeric equal
  !=        Numeric not equal
  <         Numeric less than
  >         Numeric greater than
  <=        Numeric less than or equal
  >=        Numeric greater than or equal
  eqic      Equal ignoring case
  neic      Not equal ignoring case
  mult-of   Multple of

Example returns: false:

    compare('eq','',undef);

Example returns: true:

    compare('eq','abc','abc');

Example returns: true:

    compare('ne','abc','Abc');

Example returns: false:

    compare('eq','abc',undef);

Example returns: true:

    compare('!~','abc','A');

Example returns: true:

    compare('=~','abc','a');

Example returns: true:

    compare('==',1234,1234);

Example returns: true:

    compare('>=',1234,1234);

Example returns: true:

    compare('eqic','abc','Abc');

Example returns: true:

    compare('==',undef,undef);

Example returns: false:

    compare('==',0,undef);

Example: (matches)

    my @numbers = ( 20, 1, 10, 2 );
              join ';', sort { &compare('<=>',$a,$b) } @numbers;


    1;2;10;20

sort_compare

Compare for sorting, returning 1, 0 or -1

See also compare

is_bipolar

Test to see if this is a blessed document/view object

AUTHOR

Ryan Gies (ryangies@livesite.net)

COPYRIGHT

Copyright (C) 2006-2007 by Livesite Networks, LLC. All rights reserved.

Copyright (C) 2000-2005 by Ryan Gies. All rights reserved.

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

* Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.

* The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required.

* Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.

* The name of the author may not be used to endorse or promote products derived from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE AUTHOR "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

To the best of our knowledge, no patented algorithms have been used. However, we do not have the resources to carry out a patent search, and therefore cannot give any guarantee of the above statement.

UPDATED

06/09/2007