Description:
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Expected:

Defining a constant with the `const` keyword and an expression that contains the `T_POW` (**) operator, the constant should be set to the value of the expression.

Actual:

Using the `T_POW` operator in a `const` statement produces a Parse Error with message: "Parse error: syntax error, unexpected '**' (T_POW)"

Test script:
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<?php

const MOLE = 2 ** 27;

echo MOLE;

Expected result:
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134217728

Actual result:
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Parse error: syntax error, unexpected '**' (T_POW) in example.php on line 2