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digitalmars.D.learn - Disallow implicit "conversion" from alias-types

reply Vladimirs Nordholm <v vladde.net> writes:
Hello.

I am unsure if I am going about this the right way, and if my 
question even makes sense.

In essence what I want is to have two "types" represented by a 
size_t. Here is an example of what I want think I want (but might 
be completely off)

     alias Foo = size_t;
     alias Bar = size_t;

     Foo foo = 4;
     Bar bar = foo; // i want some error like
                    // "cannot implicitly convert from type Foo to 
Bar"

My best solution is to have the types as classes to force type 
checking.

Is there a better way to do what I want here?
Nov 10 2020
parent reply Jerry <labuurii gmail.com> writes:
On Tuesday, 10 November 2020 at 11:38:30 UTC, Vladimirs Nordholm 
wrote:

 Hello.

 I am unsure if I am going about this the right way, and if my 
 question even makes sense.

 In essence what I want is to have two "types" represented by a 
 size_t. Here is an example of what I want think I want (but 
 might be completely off)

     alias Foo = size_t;
     alias Bar = size_t;

     Foo foo = 4;
     Bar bar = foo; // i want some error like
                    // "cannot implicitly convert from type Foo 
 to Bar"

 My best solution is to have the types as classes to force type 
 checking.

 Is there a better way to do what I want here?


https://dlang.org/library/std/typecons/typedef.html
Nov 10 2020
parent Vladimirs Nordholm <v vladde.net> writes:
On Tuesday, 10 November 2020 at 11:49:19 UTC, Jerry wrote:

 On Tuesday, 10 November 2020 at 11:38:30 UTC, Vladimirs 
 Nordholm wrote:

 Hello.

 I am unsure if I am going about this the right way, and if my 
 question even makes sense.

 In essence what I want is to have two "types" represented by a 
 size_t. Here is an example of what I want think I want (but 
 might be completely off)

     alias Foo = size_t;
     alias Bar = size_t;

     Foo foo = 4;
     Bar bar = foo; // i want some error like
                    // "cannot implicitly convert from type Foo 
 to Bar"

 My best solution is to have the types as classes to force type 
 checking.

 Is there a better way to do what I want here?


 https://dlang.org/library/std/typecons/typedef.html


This is exactly what I need. Thanks!
Nov 10 2020