On 05/24/2016 11:57 AM, Rowan Collins wrote:
On 24/05/2016 06:45, Jesse Schalken wrote:
I'm curious, what is it about $this that makes it special in the first
place? Can't it be a normal local variable that happens to already be
assigned at the start of a method?
There are a few things that take advantage of its specialness, e.g.
- binding a closure to an object changes the meaning of $this in a way
very different from assigning it into scope with "use($this)"
- a method declared static can detect and throw errors on anything
referencing $this
- when calling parent::foo() from an instance method, the value of
$this needs to be set appropriately on the new method; being able to
reassign $this could lead to some odd behaviour there
Python's approach is certainly valid, and leads to some different
useful properties, I'm sure, but it's a very different design, not
just a more relaxed attitude to assignment.
As of $this is a very special variable where only the engine is (or
should) be allowed to change.
I would like to ask you if it wouldn't be better to NOT define $this as
a special variable
including a lot of code to make sure this variable doesn't get re-assigned
but instead define this as a keyword like self where the syntax makes
sure it can't be re-assigned
and it's less special and simpler to learn for beginners.
I know it would be a huge BC break but for me it sounds more "right" and
could also be introduced
in parallel to $this for a long long time but without a lot of
overplayed code for $this.
Thanks,
Marc
Regadrds,
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