Limit T to int?

Question

How can I solve this error? msg?

static public class Blah
{
    public static T val<T>(this bool b, T v) { return b == true? v:0; }
}

Error

Type of conditional expression cannot be determined because there is no implicit conversion between 'T' and 'int

Answer 1

In C # there is no way to do this. You can do

where T: struct and make T be a value type, but that is still not enough.

Or you can do

default(T)which is 0 when T is int.

Answer 2

If you want T to be int, accept int rather than T. Otherwise, consider returning the default value (T) if b == false.

return b ? v : default(T);

If T is int, it will return 0. If it is a reference type, it will be zero. And further and further ..

Answer 3

generics, int?

// No need to compare b to true...
public static int val(this bool b, int v) { return b ? v : 0; }

default(T), .

public static T val<T>(this bool b, T v) { return b ? v : default(T); }

default(T) 0 int , false bool s, null ...

Answer 4

T:

public static T val<T>(this bool b, T v) { return b == true? v : default(T); }

Answer 5

v : 0 v : default(T), . int, .

Answer 6

T , :

public static int val(this bool b, int v)
{
    return b ? v : 0;
}

, , :

public static int val<T>(this bool b, T v) where T : struct
{
    return b ? v : default(T);
}

Answer 7

Srsly!

" T int", , strong-typing:

static public class Blah
{
    public static int val(this bool b, int v) { return b == true? v:0; }
}

!:)

, ?