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About implicit casting
f#

I have C# code:

class SomeType {T0, T1} { //

...

public static implicit operator T1(SomeType{T0, T1} st)

{

return st.Get{T1}(); // gets the T1 value from st container

}

...

}

In C# I can write:

var st = new SomeType{int,string}();

int v = (int)st;

In F# I write:

let v = someType |> SomeType<_,_>.op_Implicit : int

How to ease F# casting?

P.s.: where to find how to highligth code syntax in the post?

.

I have C# code: class SomeType {T0, T1} ...

I am confused - do you mean

1

class SomeType <T0, T1>

?

P.s.: where to find how to highligth code syntax in the post?

In your profile select content editor for developers It will give you some additional formatting options

By on 5/11/2009 8:20 AM ()

Nice. Found. Again:

I have C# code: 

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class SomeType <T0, T1> { // 
... 
public static implicit operator T1(SomeType<T0, T1> st) 
{ 
return st.Get<T1>(); // gets the T1 value from st container 
} 
... 
}

In C# I can write: 

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var st = new SomeType<int,string>(); 
int v = (int)st;

In F# I write: 

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let v = someType |> SomeType<_,_>.op_Implicit : int

How to simplify F# code?

By on 5/11/2009 8:32 AM ()

Here's something relatively inscrutable you can try using:

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open System.Xml.Linq

let xn = XName.op_Implicit("foo")

// a way to shorten what you write

let inline imp< ^a, ^b when ^a : (static member op_Implicit : ^b -> ^a)> arg =

    (^a : (static member op_Implicit : ^b -> ^a) (arg))

// now can write "imp<T,_> v" to implicit convert value v to type T

let xn2 = imp<XName,_> "foo"

// or like this

let xn3 : XName = imp "foo"
By on 5/11/2009 12:12 PM ()

Great. Works.

By the way, where can I read about F# "inline" constructions?

By on 5/12/2009 1:31 AM ()

Offhand I don't know any good docs - I always go and copy examples from the F# source code (prim-types.fs in the source distribution is a useful file to look at for examples of this).

By on 5/12/2009 9:09 AM ()

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