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Full Discussion: complex if statement syntax without using 'if ..' keyword in ksh.
Top Forums Shell Programming and Scripting complex if statement syntax without using 'if ..' keyword in ksh. Post 302504231 by hergp on Monday 14th of March 2011 05:24:13 AM
Old 03-14-2011
Quote:
Originally Posted by kchinnam
[ <condition> ] && <statement> || <statement>

that perfectly replaces..

if [ <condition> ]; then
<statement>
else
<statement>
fi
This is not quite true. The program flow depends on the exit code of the statement between '&&' and '||'. For example:

Code:
bash-3.00$ true && { echo 1; false; } || echo 2
1
2

If you were right, then only "1" should be printed, but as you can see, both echo statements are being executed. Whereas this executes as expected:

Code:
bash-3.00$ if true
> then
> echo 1
> false
> else
> echo 2
> fi
1

---------- Post updated at 10:24 ---------- Previous update was at 10:18 ----------

The reason is that the whole expression is evaluated as a logical expression:

Code:
A AND B OR C

If A is true, then B is evaluated. And if B is false, then the expression (A AND B) is false. Which leads to the evaluation of C. The value of the whole expression is then the value of C (true or false)

If (A AND B) is true, then value of the whole expression is true and it is not necessary to evaluate C.
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LEARN ABOUT DEBIAN

graphics::primitive::insets

Graphics::Primitive::Insets(3pm)			User Contributed Perl Documentation			  Graphics::Primitive::Insets(3pm)

NAME

       Graphics::Primitive::Insets - Space between things

DESCRIPTION

       Graphics::Primitive::Insets represents the amount of space that surrounds something.  This object can be used to represent either padding
       or margins (in the CSS sense, one being inside the bounding box, the other being outside)

SYNOPSIS

	 use Graphics::Primitive::Insets;

	 my $insets = Graphics::Primitive::Insets->new({
	   top	   => 5,
	   bottom  => 5,
	   left    => 5,
	   right   => 5
	 });

METHODS

   Constructor
       new Creates a new Graphics::Primitive::Insets.

   Instance Methods
       as_array
	   Return these insets as an array in the form of top, right, bottom and left.

       bottom
	   Set/Get the inset from the bottom.

       equal_to
	   Determine if these Insets are equal to another.

       left
	   Set/Get the inset from the left.

       right
	   Set/Get the inset from the right.

       top Set/Get the inset from the top.

       zero
	   Sets all the insets (top, left, bottom, right) to 0.

AUTHOR

       Cory Watson, "<gphat@cpan.org>"

SEE ALSO

       perl(1)

COPYRIGHT &; LICENSE
       Copyright 2008-2010 by Cory G Watson.

       This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

perl v5.12.3							    2010-08-21					  Graphics::Primitive::Insets(3pm)
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