[PHP] function and interface in parameter list?
Hi I found a function declaration in an open source project (in php5) and I could not find documantation for this. The function declaration is: public function registerComp(IComp $comp) Is it a kind of typecast? -- Cheers! Marco -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] function and interface in parameter list?
Marco Schuler wrote:
Hi
I found a function declaration in an open source project (in php5) and
I could not find documantation for this. The function declaration is:
public function registerComp(IComp $comp)
Is it a kind of typecast?
no its a type declaration (is that the correct term). it states
that $comp must be an object of class IComp (or a subclass of it).
if $comp is not anj IComp object you get a fatal error.
this only works for classes. and it does not work in conjunction
with optional params e.g:
public function registerComp(IComp $comp = null) { /**/ }
(which IMHO sucks but hey c'est la vie! :-) )
--
Cheers!
Marco
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Re: [PHP] function and interface in parameter list?
Hi
Am Dienstag, 1. Februar 2005 15:50 schrieb Jochem Maas:
Marco Schuler wrote:
Hi
I found a function declaration in an open source project (in
php5) and I could not find documantation for this. The function
declaration is:
public function registerComp(IComp $comp)
Is it a kind of typecast?
no its a type declaration (is that the correct term). it states
that $comp must be an object of class IComp (or a subclass of it).
if $comp is not anj IComp object you get a fatal error.
Where can I find this in the manual? IComp can also be an interface,
right?
this only works for classes. and it does not work in conjunction
with optional params e.g:
public function registerComp(IComp $comp = null) { /**/ }
With optional params you mean actually the variable initialisation
within the declaration, right?
--
Cheers!
Marco
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Re: [PHP] function and interface in parameter list?
Am Dienstag, 1. Februar 2005 16:07 schrieb Marco Schuler: Am Dienstag, 1. Februar 2005 15:50 schrieb Jochem Maas: Marco Schuler wrote: Hi I found a function declaration in an open source project (in php5) and I could not find documantation for this. The function declaration is: public function registerComp(IComp $comp) Is it a kind of typecast? no its a type declaration (is that the correct term). it states that $comp must be an object of class IComp (or a subclass of it). if $comp is not anj IComp object you get a fatal error. Found it out: It is called Type Hinting. http://ch2.php.net/manual/en/language.oop5.typehinting.php There is a user contributed note on that page: Type hinting allows not to specify a required interface to be supported for the object being passed. Beware, the interpreter will not give an error for that. Is it a bug in php or what is the reason? -- Cheers! -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] function and interface in parameter list?
Marco Schuler wrote:
Am Dienstag, 1. Februar 2005 16:07 schrieb Marco Schuler:
Am Dienstag, 1. Februar 2005 15:50 schrieb Jochem Maas:
Marco Schuler wrote:
Hi
I found a function declaration in an open source project (in
php5) and I could not find documantation for this. The function
declaration is:
public function registerComp(IComp $comp)
Is it a kind of typecast?
no its a type declaration (is that the correct term). it states
that $comp must be an object of class IComp (or a subclass of
it). if $comp is not anj IComp object you get a fatal error.
Found it out: It is called Type Hinting.
ah yes! although ClassType Hinting would be more truthful
http://ch2.php.net/manual/en/language.oop5.typehinting.php
There is a user contributed note on that page:
Type hinting allows not to specify a required interface to be
supported for the object being passed. Beware, the interpreter will
not give an error for that.
Is it a bug in php or what is the reason?
I don't even understand what the guy was trying to say in the user
comments - let alone if its a bug or a feature!
with regard to type hinting with Interfaces - I have no idea offhand,
but by using my hands I found out in about 30 seconds... I wrote the bit of
code below, if you run it you will find out for yourself whether is works ;-)
php -r '
interface MyInt { function doIt(); }
class MyObj implements MyInt { function doIt() { echo boo; } }
function goGo(MyInt $x) { $x-doIt(); }
goGo(new MyObj);
'
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Cheers!
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