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Remove example of odd behaviour of PHP constants which I can't reproduce. It

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seems highly likely it's been fixed in PHP now, as the example dates from PHP4
days.


git-svn-id: https://swig.svn.sourceforge.net/svnroot/swig/trunk@12750 626c5289-ae23-0410-ae9c-e8d60b6d4f22
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Olly Betts 2011-06-24 17:18:43 +00:00
commit e3b5627ab5
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Doc/Manual/Php.html
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@ -249,60 +249,6 @@ evaluates to true, rather than the value of the constant which would
be false. This is a feature! be false. This is a feature!
</p> </p>
<p>
The second 'feature' is that although constants are case sensitive (by
default), you cannot declare a constant twice with alternative
cases. E.g.,
</p>
<div class="code">
<pre>
%module example
#define TEST Hello
#define Test World
</pre>
</div>
<p>
accessed from PHP,
</p>
<div class="code">
<pre>
include("example.php");
echo TEST, Test;
</pre>
</div>
<p>
will output "Hello Test" rather than "Hello World". This is because
internally, all constants are stored in a hash table by their lower
case name, so 'TEST' and 'Test' will map to the same hash element
('Test'). But, because we declared them case sensitive, the Zend
engine will test if the case matches with the case the constant was
declared with first.
</p>
<p>
So, in the example above, the TEST constant was declared first, and
will be stored under the hash element 'test'. The 'Test' constant will
also map to the same hash element 'test', but will not overwrite
it. When called from the script, the TEST constant will again be
mapped to the hash element 'test' so the constant will be
retrieved. The case will then be checked, and will match up, so the
value ('Hello') will be returned. When 'Test' is evaluated, it will
also map to the same hash element 'test'. The same constant will be
retrieved, this time though the case check will fail as 'Test' !=
'TEST'. So PHP will assume that Test is a undeclared constant, and as
explained above, will return it as a string set to the constant name
('Test'). Hence the script above will print 'Hello Test'. If they were
declared non-case sensitive, the output would be 'Hello Hello', as
both point to the same value, without the case test taking place. (
Apologies, this paragraph needs rewriting to make some sense. )
</p>
<H3><a name="Php_nn2_2"></a>31.2.2 Global Variables</H3> <H3><a name="Php_nn2_2"></a>31.2.2 Global Variables</H3>