On 04/03/2013 16:05, Alexander Klenin wrote:
Anonymous functions (with good syntax, of course) fall in this category.
The world recognized that fact -- rather slowly, to be sure, but
remember that "while"s and "for"s
also took decades to be accepted as standard constructs.
I am not going to ask for proof of this statement (as for example in
quotation of literature on the topic).
For the arguments sake, let's assume the above.
No, my proposal (which was made in the previous thread in this topic)
is following (all-caps denotes non-terminal):
1.1) A function of the form
function NAME(PARAMS): RETURNTYPE; begin Result := EXPRESSION; end;
can be shortened to
function NAME(PARAMS): RETURNTYPE as EXPRESSION
IMHO that is not a good idea. It adds an additional construct, that
every reader must know how to read. It does not add/save enough to be
needed.
If you look for the most natural, pascal like (ignoring the part that
declaring a function inline, IMHO is not that)
ATree.VisitPreorder(TVisitor(Result := X + 5);
ATree.VisitPreorder(TVisitor(begin Result := X + 5; end);
You are type casting the code, into a procedure of the given type.
There is certainly a merit in that, but it violates another Pascal
"basic principle" -- "prefer keywords to symbols".
We could also use the new, have a constructor for everything
(TArray.Create) style. Personally, the idea appals me, but
TVisitor.Create(Result := x + 5)
Another way to avoid the "as"
lambda(TVisitor) .... end
lambda acts as "begin" to the block, so there always must be an end.
Also, note that you can not omit Result assignment,
since ATree.VisitPreorder(TVisitor(X + 5)); is syntactically ambiguous.
So it becomes
ATree.VisitPreorder(TVisitor(Result := X + 5));
vs
ATree.VisitPreorder(lambda TVisitor as X + 5);
See above. The omission "of Result :=" is IMHO not desirable.
Finally, I disagree with unbalanced parenthesis -- but that's probably a typo?
yes
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