Web студия "GrandView"

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Объявленные в ядре константы -- Константы, объявленные в ядре PHP, Zend, и SAPI-модулях
Стандартные константы -- Константы, объявленные в PHP по умолчанию

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Предопределенные константы

josharian at gmail dot com
18-Oct-2007 08:56


@docey:



Unfortunately, that will not work -- PHP will convert (PHP_INT_MAX+1) to a float.



At least on my system, the minimum integer size is -PHP_INT_MAX - 1. I would say that that should be reliable elsewhere, but PHP ints have known portability issues -- see e.g. http://preview.tinyurl.com/ywh7ya



Confirm this way:



<?php



echo gettype(PHP_INT_MAX) . "\n";

echo gettype(PHP_INT_MAX + 1) . "\n";

echo gettype(-PHP_INT_MAX) . "\n";

echo gettype(-PHP_INT_MAX - 1) . "\n";

echo gettype(-PHP_INT_MAX - 2) . "\n";



?>



On my system this yields:



integer

double

integer

integer

double



It would be nice to have a PHP_INT_MIN, though. Even better would be to have reliable, predictable data types...

docey
30-Aug-2007 01:22


a simple way of getting the minium allowed integer value is by adding 1 to the PHP_INT_MAX constant value. it causes the signed integer to roll over from the maxium integer size to the minium integer size.

Tea Bore
28-Sep-2005 12:09


Use get_defined_constants() to retrieve these constants.



<?php



print '<pre>';

print_r(get_defined_constants());

print '</pre>';



?>

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Last updated: Sun Nov 4 15:20:50 2007 PST