php - adding parameters to overriden method E_STRICT observation -

php - adding parameters to overriden method E_STRICT observation -

it appears (php 5.3) if overriding class method, it okay to can add together additional parameters, long have default values.

for example, consider class:

class test1 { public function stuff() { echo "hi"; } }

the next class extends "test1" , produce e_strict warning.

class test2 extends test1 { public function stuff($name) { echo "hi $name"; } }

but, next not produce e_strict warning.

class test3 extends test1 { public function stuff($name = "") { echo "hi $name"; } }

while class "test3" doesn't produce e_strict warning, have been under impression php not allow method signatures overloaded overridden. so, have ask. observation bug/flaw or correct intended behavior?

further, if default argument parameter okay, why non-default argument parameter not okay?

if add together non-defaulted parameter overridden method, subclass no longer satisfies contract defined superclass. cannot correctly phone call test2->stuff(), because method expects parameter - superclass says should able phone call without one. hence e_strict warning.

if add together defaulted parameter though, can still phone call test3->stuff() (from example) - superclass expects - , contract not broken. in fact, adding optional parameter, have extended it.

php oop coding-style