TalkPHP - View Single Post - Is the double colon var resolution valid in an Argument?

Salathe · 01-21-2008, 11:58 AM

The simple answer to your question is, no. Trying to use a constant of any kind (class or global) will result in a parse error, "syntax error, unexpected T_CONST, expecting T_VARIABLE". The error is pretty self-explanatory, the PHP engine expects a standard, normal, garden-variety variable (a reference or otherwise) as an argument.

If you were to try this with a static variable (public static $test = ... and self::$test as the function argument) then you would also get a parse error, this time saying: "syntax error, unexpected T_PAAMAYIM_NEKUDOTAYIM, expecting '&' or T_VARIABLE". Again it's clear that PHP really, really only wants a regular variable in there (the T_PAAMAYIM_NEKUDOTAYIM is just a constant for the '::' or T_DOUBLE_COLON operator).

If you tried to use an object property as the argument ($this->test) then I think you can guess the likely outcome from the examples given so far.

In short, you can only use a normal variable ($test) or reference (&$test) as arguments.

01-21-2008, 11:58 AM	#3 (permalink)
Salathe Moderateur Join Date: Apr 2007 Posts: 1,393 Thanks: 5	The simple answer to your question is, no. Trying to use a constant of any kind (class or global) will result in a parse error, "syntax error, unexpected T_CONST, expecting T_VARIABLE". The error is pretty self-explanatory, the PHP engine expects a standard, normal, garden-variety variable (a reference or otherwise) as an argument. If you were to try this with a static variable (`public static $test = ...` and `self::$test` as the function argument) then you would also get a parse error, this time saying: "syntax error, unexpected T_PAAMAYIM_NEKUDOTAYIM, expecting '&' or T_VARIABLE". Again it's clear that PHP really, really only wants a regular variable in there (the T_PAAMAYIM_NEKUDOTAYIM is just a constant for the '::' or T_DOUBLE_COLON operator). If you tried to use an object property as the argument (`$this->test`) then I think you can guess the likely outcome from the examples given so far. In short, you can only use a normal variable (`$test`) or reference (`&$test`) as arguments.