adding custom keywords to c#

[Dan]

Hi everybody,

is it possible to add new keywords in c#, in order to improve functionality?
just as
(using IDisposableImplementer = new IDisposableImplementer())
{
// use the IDisposableImplementer
}
first thing that pops in my mind - even though may seem trivial - is for
automatically setting the cursor to busy before a lengthy operation and
resetting to default afterwards; just using a construct similar to "using".

Thank you,
Daniel

[Daniel O'Connell [C# MVP]]

"Dan" <Da*@discussions.microsoft.com> wrote in message
news:45**********************************@microsof t.com...

Hi everybody,

is it possible to add new keywords in c#, in order to improve
functionality?
just as
(using IDisposableImplementer = new IDisposableImplementer())
{
// use the IDisposableImplementer
}
first thing that pops in my mind - even though may seem trivial - is for
automatically setting the cursor to busy before a lengthy operation and
resetting to default afterwards; just using a construct similar to
"using".

You can't add keywords, no, but you can abuse using to do this(although I'm
not sure if it is a good idea or not...)

Simply create a disposable class that sets the cursor to busy in its
constructor(you'd have to pass the form you want to change the cursor on of
course) and unsets it in its Dispose method. Then when you use it in a using
block you get the effect you want.

[Jon Skeet [C# MVP]]

Dan wrote:

is it possible to add new keywords in c#, in order to improve functionality?
No. You could get hold of the sources for the Mono C# compiler and
modify those, of course - but you'd have a job getting Visual Studio to
use that!
just as
(using IDisposableImplementer = new IDisposableImplementer())
{
// use the IDisposableImplementer
}
first thing that pops in my mind - even though may seem trivial - is for
automatically setting the cursor to busy before a lengthy operation and
resetting to default afterwards; just using a construct similar to "using".

That *certainly* shouldn't be part of the language - but you can easily
"fake" it with your own class which implements IDisposable anyway:

using (new CursorChanger())
{
.....
}

Just make your CursorChanger change the cursor to busy, and then reset
it in Dispose.

Jon

[Dan]

The example with "using" was just an example;
I meant a more generic way to extend either the .NET Framework or C#...

AFAIK, in .NET 3.0 it will be possible to extend primitive types, like int,
with new functionality - much like in Smaltalk...

"Jon Skeet [C# MVP]" wrote:

Dan wrote:

is it possible to add new keywords in c#, in order to improve functionality?

No. You could get hold of the sources for the Mono C# compiler and
modify those, of course - but you'd have a job getting Visual Studio to
use that!

just as
(using IDisposableImplementer = new IDisposableImplementer())
{
// use the IDisposableImplementer
}
first thing that pops in my mind - even though may seem trivial - is for
automatically setting the cursor to busy before a lengthy operation and
resetting to default afterwards; just using a construct similar to "using".

That *certainly* shouldn't be part of the language - but you can easily
"fake" it with your own class which implements IDisposable anyway:

using (new CursorChanger())
{
.....
}

Just make your CursorChanger change the cursor to busy, and then reset
it in Dispose.

Jon

[Jon Skeet [C# MVP]]

Dan wrote:

The example with "using" was just an example;
Yes, but it shows that often there's already a way of achieving a
desired effect without changing the language at all.
I meant a more generic way to extend either the .NET Framework or C#...

AFAIK, in .NET 3.0 it will be possible to extend primitive types, like int,
with new functionality - much like in Smaltalk...

Well, not really. It will be possible to *pretend* that a type (any
type) has a method, by effectively redirecting calls to that method to
a static method. It's only syntactic sugar for what's already
available.

However, that's not going to allow you to add your own keywords etc.
Personally, I'm glad about that - it means that when I see some C#, I
know what it means, rather than everyone having their own subtly
different dialect.

Jon