Re: D 1.076 Alpha for Windows 64 bits, works with VS 2010
On 06/10/12 20:38, Walter Bright wrote: On 9/30/2012 9:35 PM, Andrej Mitrovic wrote: On 10/1/12, Walter Bright newshou...@digitalmars.com wrote: Also, consider that in C++ you can throw any type, such as an int. There is no credible way to make this work reasonably in D, as exceptions are all derived from Exception. Is that a bug or a feature? :) It's a feature, and I'm not joking. What is the compelling use case for throwing an int? How could that possibly fit into some encapsulation model? What if library A throws an int, and library B does? Now you catch an int - which did it come from? You've got no clue. It's indistinguishable from garbage. Just imagine how much fun could be had, if D let you throw sqrt(17.0) + 37.919i.
Re: Remus
As promised, a little description of Remus. :)
Not Null references:
I chose this syntax: int b = a; because I like it in C++. This
syntax is recognized by Remus and is converted to: Ref!(int) b =
a;
If you must give a reference to a function or other things like
that, you can write:
[code]
Foo obj = new Foo();
some_function(@obj)
[/code]
instead of
[code]
Foo obj = new Foo();
{
Foo robj = obj;
some_function(robj);
}
[/code]
Namespaces: You can declare a namespace this way:
[code]
namespace io {
void print() {
writeln(foo);
}
}
[/code]
you _cannot_ use it without explicit use statement (will maybe
change). So you must write
[code]use io;[/code] to use _all_ methods from io, or, like
import, [code]use io : print[/code] or [code]use io : write =
print;[/code]
use statements are converted to one or more alias' and
namespaces to (mixin) templates.
not null safe invocation:
If you have an object which can be null, you can write:
obj?.print(); the print method is only called, if obj is not null.
It works even with more than one '?': obj?.getOtherObj?.print();
but then you have to take care of some special weakneses:
Until now you can not write obj?.getOtherObj()?.print() because
the parent's aren't recognized as valid identifiers for '?'.
So you must use properties or this workaround:
[code]
Foo otherObj = obj?.getOtherObj(); // otherObj is null if obj is
null
otherObj.print();
[/code]
Furthermore you cannot use '?' in the middle or end, or with
breaks.
So these are valid: a?.b.c and this a?.b?.c but these a.b?.c and
a?.b.c?.d not.
I described some more examples, do's and don't's on my website.
Stack Instances:
There aren't many words for: if you need a stack instance, write:
local Foo f = new Foo(); it's more or less the same as scope.
My next version will contain the elvis operator:
[code]
Foo obj = otherObj.get() ?: null;
if otherObj.get() is _not_ null, it will assign to obj, otherwise
obj will be assigned with null.
[/code]
And maybe cast's with 'as'. But my main interests are to fix the
bugs and weakneses.
That's it. Sorry for the few words, but I'm a bit busy right now.
If you have questions or suggesstions you can write it here,
I will read it every evening.
Re: Remus
Namespace:
Not Null references:
I chose this syntax: int b = a; because I like it in C++. This
syntax is recognized by Remus and is converted to: Ref!(int) b
= a;
If you must give a reference to a function or other things like
that, you can write:
[code]
Foo obj = new Foo();
some_function(@obj)
[/code]
instead of
[code]
Foo obj = new Foo();
{
Foo robj = obj;
some_function(robj);
}
This seems far from being well designed not-nullable
pointers/class references :-(
[/code]
Namespaces: You can declare a namespace this way:
[code]
namespace io {
void print() {
writeln(foo);
}
}
[/code]
you _cannot_ use it without explicit use statement (will
maybe change). So you must write
[code]use io;[/code] to use _all_ methods from io, or, like
import, [code]use io : print[/code] or [code]use io : write =
print;[/code]
use statements are converted to one or more alias' and
namespaces to (mixin) templates.
But what are they useful for?
Stack Instances:
There aren't many words for: if you need a stack instance,
write: local Foo f = new Foo(); it's more or less the same as
scope.
scope was removed for certain reasons, are those reasons not
valid for local?
Bye,
bearophile
Re: Remus
On Tuesday, 9 October 2012 at 19:34:01 UTC, Namespace wrote: Stack Instances: There aren't many words for: if you need a stack instance, write: local Foo f = new Foo(); it's more or less the same as scope. What's the difference between this and std.typecons.scoped, except for alignment and syntax?
Re: Remus
This seems far from being well designed not-nullable pointers/class references :-( And why not? In my test cases, they fulfilled their task / purpose very well. And you ask for what namespaces are usefull? Aren't you miss them? I do, and so I implement them. You can already write namespaces in D, but you must use a (mixin) template (so you have these ugly parents) and for using you have to write: alias tpl_nspace!().print print or directly: tpl_nspace!().print. And that's ugly (because of '!()') and annoying IMO. For what local is good for and whats the differences between my version and scoped from dmd I will tell later, but as you can see: you have to write: local Foo f = new Foo(); what is more intuitive as Scoped! Foo f = scoped!Foo(); IMO.
