The Pascal 'with' statement is among the most hated features of

Pascal and was not copied in successor languages like Ada or Modula-2.

It was typically replaced by record constructors, such as

�� Book1 := Book[title���� : 'C Programming';

������������������������������ author�� : 'Nuha Ali ';

������������������������������ subject : 'C Programming Tutorial';

������������������������������ book_id : 6495407];

which happens to be Pascal (ISO10206).

In

�� self classes do: [:class |
	| metaclass |
	metaclass := class metaclass.
	metaclass xxxx.
	mataclass yyyy.
�� ]
"metaclass" is a a block temporary, not an instance variable,
and
���� self classes do: [:each | (each metaclass) xxxx; yyyy].
suffices.

We observe that
�� [:x1 ... :xn | ...] value: e1 ... value: en
is nothing other than a LET expression wearing a funny hat
and should be inlined by a compiler -- mine does -- and that
�� e1 in: [:x1 | ...]
is just a "flipped" version of [:x1 | ...] value: e1, so
there's no reason why a compiler shouldn't inline that.
We also observe that
�� e0 m1; ... ; mn
can -- at least in my experience -- be most simply implemented
as [:t | t m1. ... t mn] value: e0
followed by the usual inlining of that.
So we might expect that some day
�� self classes do: [:each | each metaclass in: [:t | t xxxx. t yyyy]]
would generate the *same* code as the cascaded version.

Right now, do whichever is clearer.

On Tue, 5 Mar 2019 at 02:07, Tim Mackinnon <tim@testit.works> wrote:

I��ve noticed that as we��ve progressed there has been a move to more concise and fluid code - e.g. I quite like the new String streaming stuff

e.g.��

^ String
streamContents: [ :stream |��
stream nextPut: ��. ]

So I was wondering why we don��t have a construct like Pascals with ��to avoid Book1.title, Book1.author etc.
(* book 1 specification *)
With Book1 do
begin
   title  := 'C Programming';
   author := 'Nuha Ali '; 
   subject := 'C Programming Tutorial';
   book_id := 6495407;
end;
I often find it a bit tedious with code like the following which then needs an instvar...

self classes do: [ :class |
| metaclass |
metaclass := class metaclass.
metaclass xxxx.
mataclass yyyy.
]

I��m wondering why we don��t have #with:do: ��

class with: class metaclass do: [:metaclass |
metaclass xxx.
]

But when such things aren��t there - there is usually a good reason and I��m curious �� this said, there are all kinds of other such tricks (which I rarely use that I keep coming across).

Tim