Edit report at https://bugs.php.net/bug.php?id=49526&edit=1

 ID:                 49526
 Comment by:         phpdev at zerocue dot com
 Reported by:        president at basnetworks dot net
 Summary:            C# style property get/set syntax
 Status:             Open
 Type:               Feature/Change Request
 Package:            Scripting Engine problem
 Operating System:   *
 PHP Version:        *
 Block user comment: N
 Private report:     N

 New Comment:

An "as implemented" document has been created here:
https://wiki.php.net/rfc/propertygetsetsyntax-as-implemented

Only thing remaining to be implemented is static accessors.


Previous Comments:
------------------------------------------------------------------------
[2010-10-28 00:48:47] rayro at gmx dot de

I also recommend this but i have a little idea too:

1. Most of the time i use get<VariableName>() syntax and I have to write new 
functions for that (or using __call or __set), because i protect the properties 
with private or protected to protect for writing them.
2. Most of all the code is ugly or has limitations using readonly/writeonly 
properties with __get(&$v) or __set($v,&$c) by reference.
3. It is not perfectly clean to write less code with __get or getter/setter if 
only want to protecting them... And less code matters!

I would like to see a new, or 2 new keywords, e.g. "readonly" and "writonly", 
because the code will look smoother and i dont have to make the use of magic 
methods... Or some own designed errors for that...

Now an simple example:
======================

<?php
class A
{
  /** the following syntax is just invented  **/
  static readable protected $foo = 1;
  static writable protected $bar = 2;
}

A::$foo++; // raises error "variable is not writeable from this context"
echo(A::$foo); // will simple echo $foo
A::$bar++; // will increment $bar to 3
echo(A::$bar); // raises error "variable is not readable from this context"
?>

( what about is_readable() or is_writable() for that? )
I dont think that these functions will be used, so only Reflection should be 
extended...

and now, instead of the current syntax:
======================================

<?php
class A
{
  static protected $foo = 1;
  static protected $bar = 1;
  function __get($v) {
    if ($v == 'bar') {
      trigger_error('$bar is not readble from this context',E_USER_ERROR);
    }
    return $this->$v;
  }
  function __set($v, $c)
  {
    if ($v == 'foo') {
      trigger_error('$foo is not writable from this context',E_USER_ERROR);
    }
    $this->$v = $c;
    return true;
  }
}
?>

get/set syntax will be nice but also nasty if only read/writablity is desired...

this can be confusing as this:
==============================
<?php
class A
{
  /** the following syntax is just invented  **/
  static protected $foo {
    function __get() {
      return $this->foo;
    }
    function __set() {
      trigger_error('$foo is not writable from this context',E_USER_ERROR);
    }
  } = 1;
  static protected $bar {
    function __get() {
      trigger_error('$bar is not readable from this context',E_USER_ERROR);
    }
    function __set() {
      $this->bar = 1;
      return true;
    }
  } = 2;
}
?>

think about it... many developers will waive the old way or functions like 
getVarname and setVarname... and for all other, getter/setter will be nice as 
described in the rfc...

------------------------------------------------------------------------
[2009-09-13 19:56:24] president at basnetworks dot net

For reference, the RFC for this feature request now exists at this URL:

http://wiki.php.net/rfc/propertygetsetsyntax

------------------------------------------------------------------------
[2009-09-13 04:24:08] president at basnetworks dot net

Hi Kalle,

Thanks for the information.  I will follow your instructions and start working 
on the RFC over the next week(s).  Also, thanks for the link about the 
Developer Summit, but it does not show the outcome of the discussion, am I able 
to find that anywhere?

------------------------------------------------------------------------
[2009-09-12 12:22:19] ka...@php.net

Hey

The best way to request this feature is to write an RFC in our wiki at:
http://wiki.php.net/rfc/

Request an account at:
http://wiki.php.net/start?do=register

And then send an email to the webmaster list (php-webmas...@lists.php.net) 
requesting write access to the rfc namespace and repost this feature request as 
an RFC. When you are done, start a new thread on internals 
(intern...@lists.php.net) explaining your RFC.

As for reference, this idea was discussed at the last PDM in May, see:
http://wiki.php.net/summits/pdmnotesmay09#php_6 point #16

------------------------------------------------------------------------
[2009-09-11 01:02:26] president at basnetworks dot net

Description:
------------
I would like to request a C# style get/set syntax (called a property in C#) for 
PHP.  Basically, it looks and acts like a class member/variable from outside 
the class, but it is actually a set of two methods.  It can be used to provide 
only read or write access to a class member, do pre or post processing on a 
member, or be completely dynamic like a set of class methods.

A property contains two methods between braces, named get and set.  get must 
always have a return statement, while set has a magic variable "value" or 
"$value" which is the variable that was passed to the property.  Either method 
can be omitted to make the property read-only or write-only.

The same effect can be achieved by creating a GetVar() and SetVar() method to 
create a sudo-property "var", although it is by far much clumsier and less 
intuitive.

I also realize the same effect received outside the class can be achieved using 
the __get() and __set() methods, but these methods are only really useful in a 
small instance of situations, like giving access to an internal array as though 
each index is a property.  These magic methods are not at all useful for using 
on an individual property basis, and it gets worse when inheritance is 
introduced.

The C# syntax is as follows:

class TimePeriod
{
    private double seconds;

    public double Hours
    {
        get { return seconds / 3600; }
        set { seconds = value * 3600; }
    }
}



The PHP syntax would be similar to the following:

class TimePeriod
{
    private $seconds;

    public property Hours
    {
        get { return $this->seconds / 3600; }
        set { $this->seconds = $value * 3600; }
    }
}



You would use it exactly the same as a public class member:

$time = new TimePeriod();
$time->Hours = 24;
echo $time->Hours;



As opposed to the alternative:
$time = new TimePeriod();
$time->SetHours(24);
echo $time->GetHours();



Additionally, the get and set methods can have separate visibilities like in 
the following example where get is public and set is protected:

public property Name
{
    get { return $this->name; }
    protected set { $this->name = $value; }
}



There is another ticket that is similar but not the same thing here:
http://bugs.php.net/bug.php?id=34194

It suggests separate getter/setter methods, which in my opinion are much less 
intuitive.  I believe that following the C# format would help to keep a 
standard format, and would be the least confusing.

The poster of that bug also fails to realize that separate visibility levels 
can be achieved for properties using the C# syntax, as shown above.



The C# documentation on properties is available here:
http://msdn.microsoft.com/en-us/library/x9fsa0sw%28VS.80%29.aspx

The C# documentation on Asymmetric Accessor Accessibility for properties is 
available here:
http://msdn.microsoft.com/en-us/library/75e8y5dd%28VS.80%29.aspx



------------------------------------------------------------------------



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