Description:
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In PHP 5.6, const supports static expression.

But it still does not support dynamic expression.

So please implement the ability to use dynamic expressions when using const.

I think that const should replace define() entirely.

const is much more readable and natural than define().



Test script:
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<?php
const PI = atan(1)*4;
const RANDOM = rand();

echo PI . "\n";
echo RANDOM . "\n";


Expected result:
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3.141592653589793
445


Actual result:
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Parse error: syntax error, unexpected '(', expecting ',' or ';' in C:\Users\hack
s_000\Desktop\test.php on line 2