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Full Discussion: Best practice for bracket comparisons?
Top Forums Shell Programming and Scripting Best practice for bracket comparisons? Post 302386535 by Corona688 on Tuesday 12th of January 2010 04:42:10 PM
Old 01-12-2010
Quote:
Originally Posted by tlarkin
Thanks for your reply, but still got a few questions...

According to this document, which I have used to teach myself shell programming, [[ and [ have different abilities in bash.
Yes, BASH has many extensions on the standard shell. But you can't depend on those extensions anywhere else.

As for numerical and string equality being identical, well -- given the same number base and no leading zeroes or extraneous sign symbols, a string comparison is no different than a numerical comparison. I've tried various things to trip them up, things like comparing positive and negative zero... it always acts just like a string comparison whether its one or two equals.
 

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LEARN ABOUT PHP

strnatcasecmp

STRNATCASECMP(3)							 1							  STRNATCASECMP(3)

strnatcasecmp - Case insensitive string comparisons using a ";natural order" algorithm

SYNOPSIS

       int strnatcasecmp (string  $str1, string  $str2)

DESCRIPTION

	This  function	implements  a  comparison algorithm that orders alphanumeric strings in the way a human being would. The behaviour of this
       function is similar to strnatcmp(3), except that the comparison is not case sensitive. For more	information  see:  Martin  Pool's  Natural
       Order String Comparison page.

PARAMETERS

	      o $str1
		- The first string.

	      o $str2
		- The second string.

RETURN VALUES

	Similar  to  other string comparison functions, this one returns < 0 if $str1 is less than $str2 > 0 if $str1 is greater than $str2, and 0
       if they are equal.

SEE ALSO

       preg_match(3), strcmp(3), strcasecmp(3), substr(3), stristr(3), strncasecmp(3), strncmp(3), strstr(3), setlocale(3).

PHP Documentation Group 													  STRNATCASECMP(3)
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