... like in Ruby

Is it possible to extend int (simple types) to be able do something like in this code, written in Ruby

3.times { print "X " }

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... like in Ruby

simmy
Sure, you can have

static public IEnumerable<Int32> Yield(this Int32 subject)
{
for (int i = 1; i <= subject; i++)
yield return i;
}

and then use 3.Yield() to get an enumerable containing [1, 2, 3].
Habib Heydarian MSFT
Lovely!
Mark Ashton
Making it possible to extend Int32 answer my question, thanks.

I guess you can yield the values as well to be able to project an int to an enumerable
CG_JCAHO
Yeah, I understand. But what real world scenario would involve doing an operation on a literal value I'm not picking on the feature, but rather asking a theoretic question. Is the ability to do it against a literal just a "you get it for free anyway" side effect of type extensions or is there a scenario where someone would really want to do this

Brian
Queue256
Brian_Kramer wrote:

the 3.Times example is pretty cool. I'm curious: what kind of real-world scenario would call for operating on a literal like this

Hi Brian

As a real world example you could take anything where you need a loop. The idea is to avoid an ordinary for next loop with this structure. the 3.Times example shows how a loop could look like in a purely object oriented program if we had the possibility of passing code blocks. A similar idea would be to do something like that for collections:

aCollection.DoForEach(some code)

Currently you can do this with delegates, but the delegate overhead makes it actually longer than an ordinary loop. This delegate overhead will disappear with the C# 3.0 compiler, which will resolve such passed code blocks in anonimous methods.
TenBaseT
For the moment, you have to write it like that:

delegate void Procedure();

static class TestExtensions
{
static public void Times(this Int32 subject, Procedure procedure)
{
for (int i = 1; i <= subject; i++)
procedure();
}
}

Which allows you to write:
3.Times(delegate {Console.WriteLine("X");});
Mariano Trinanes
Hi

What about the lambda function in C# Can they be used in order to make the code more like the ruby example By the way, will the lambda function be available in VB, too
Jobria
the 3.Times example is pretty cool. I'm curious: what kind of real-world scenario would call for operating on a literal like this

Brian
Matt Scott -- MSFT
We'll definitely have support for them so that we can support LINQ in general. However, the exact form is yet to be determined...

Paul
VB Team
... like in Ruby

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