Suggestion: echo function(var)[0];

Felipe Pena schreef:

Hi!

2010/6/4 Stas Malyshev smalyshev@sugarcrm.com

Hi!

function call chaining (f()() if f() returns function), and array

dereferencing (f()[0]) - (Stas)

I did patch for f()() - it's referenced at
http://wiki.php.net/rfc/fcallfcall - but not for f()[] - didn't have time
for that yet.

It should not be too hard to do, one just has to be careful with refcounts
so that the returned result could be freed properly and without hurting the
referred element.

I wrote a patch, but I cannot test all cases, so I'm not sure if is okay at
all.

What about this approach: http://felipe.ath.cx/diff/array_dereference.diff ?

If the patch is really that easy I'm gonna kill someone. (Or marry you,
depending on my mood :))

Hi all,

2010/6/5 Felipe Pena felipensp@gmail.com

Hi!

2010/6/4 Stas Malyshev smalyshev@sugarcrm.com

Hi!

function call chaining (f()() if f() returns function), and array

dereferencing (f()[0]) - (Stas)

I did patch for f()() - it's referenced at
http://wiki.php.net/rfc/fcallfcall - but not for f()[] - didn't have time
for that yet.

It should not be too hard to do, one just has to be careful with refcounts
so that the returned result could be freed properly and without hurting the
referred element.

I wrote a patch, but I cannot test all cases, so I'm not sure if is okay at
all.

What about this approach: http://felipe.ath.cx/diff/array_dereference.diff?

I've updated the patch, now it works with method call as well.

Example:
<?php

class foo {
public $x = 10;

public function bar() {
$x = array();
$x[] = 3;
$x[] = array(1, 5);
$x[] = new foo;
return $x;
}
}

$foo = new foo;
var_dump($foo->bar()[2]->bar()[0]); // 3
var_dump($foo->bar()[2]->bar()[1]); // array(0 => 1, 1 => 5)
var_dump($foo->bar()[2]->bar()[1][1]); // 5
var_dump($foo->bar()[2]->bar()[2]->x); // 10

function test($arr) {
$x = $arr;
return $x;
}

$array = array(1, new foo);
var_dump(test($array)[0]); // 1
var_dump(test($array)[1]->bar()[0]); // 3
var_dump(test($array)[1]->bar()[2]); // object(foo)

http://felipe.ath.cx/diff/array_dereference.diff

Thanks.

--
Regards,
Felipe Pena

I don't understand what is holding PHP back from having this syntax.

Tig said:
<?
$tmp = getimagesize('./path/to/image');
echo $tmp[1];
?>

The need to assign the trivial variable $tmp first is completely arbitrary.
Is it not a design goal somewhere that languages should allow the greatest
degree of literal expression possible, consistent with existing syntax &
semantics rules?

I am new here but would be interested in helping with a patch (+ hopefully
another RFC) for this. What exactly are the specific arguments against array
dereferencing?

• Harrison

On Fri, Jun 4, 2010 at 4:19 PM, mathieu.suen mathieu.suen@easyflirt.comwrote:

Hi

Why not something more generic.
Someone could think of a ValueNode.

Then it could be use for object, array, any primitive type ...

I will take the ValueNode as a non terminal grammar node.
So first we could do that:

ValueNode->method();
ValueNode::sMethod();
ValueNode[];
foo(ValueNode);
echo ValueNode;
$e = ValueNode;
...

And a ValueNode could be define as:

ValueNode :

 NewStatement

| FunctionCall
| PrimitiveValue
| '(' ValueNode ')'
| ...;

This would allow all this syntax:

(new A())->foo();
foo(new A());
foo->bar()[1];
foo()[5];

and many others.

Hi Tig

2010/6/4 Tigtigger.on@gmail.com:

Would be at all possible to implement this kind of shortcut?

Its called array-dereferencing and it was proposed countless times,
including by myself. There is an RFC for this[1] and it was planned on
the old PHP6 todo at the PDT[2].

[1] http://wiki.php.net/rfc/functionarraydereferencing
[2] http://wiki.php.net/summits/pdmnotesmay09#php_6 (see point #13)

--Mathieu Suen

Not an expert in this area, but does this mechanism limit you to using
single dimensional arrays?

Of course not as soon as you add array access to a ValueNode

ValueNode

..
| ArrayAccess
...;

This is very simple and it can refactor greatly the parser.

-- Mathieu Suen