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digitalmars.D.learn - Passing a type as paramter to super

reply Marc <jckj33 gmail.com> writes:
For code generation purposes, I'd like to pass a type name to 
base class. I'm not sure if it's supported, I didn't find 
anything at documentation for class constructor but it does 
compile:


 class A {
 	static {
 		int a, b;
 	}
 
 	this(T)() {
 
 	}
 }


then do something like this:


 class B {
  this() {
    super!B;
  }
}


but I got the error:


 found ! when expecting ; following statement
Jan 04 2018
next sibling parent reply Marc <jckj33 gmail.com> writes:
On Thursday, 4 January 2018 at 19:16:03 UTC, Marc wrote:

 For code generation purposes, I'd like to pass a type name to 
 base class. I'm not sure if it's supported, I didn't find 
 anything at documentation for class constructor but it does 
 compile:


 class A {
 	static {
 		int a, b;
 	}
 
 	this(T)() {
 
 	}
 }


 then do something like this:


 class B {
  this() {
    super!B;
  }
}


 but I got the error:


 found ! when expecting ; following statement




sorry I mean define class b as following:


 class B : A {
  this() {
    super!B;
  }
}
Jan 04 2018
parent Steven Schveighoffer <schveiguy yahoo.com> writes:
On 1/4/18 2:19 PM, Marc wrote:

 On Thursday, 4 January 2018 at 19:16:03 UTC, Marc wrote:

 For code generation purposes, I'd like to pass a type name to base 
 class. I'm not sure if it's supported, I didn't find anything at 
 documentation for class constructor but it does compile:


 class A {
     static {
         int a, b;
     }

     this(T)() {

     }
 }


 then do something like this:


 class B {
  this() {
    super!B;
  }
 }


 but I got the error:


 found ! when expecting ; following statement




 
 sorry I mean define class b as following:
 

 class B : A {
  this() {
    super!B;
  }
 }


 


AFAIK, you can't explicitly use template parameters for constructors, it 
has to be IFTI. Ali has the right idea for capturing the type of this.

But it only goes one level deep, it doesn't give you the full derived 
type if there are 2 or more levels.

Note, you may want to simply define a separate non-constructor for this 
purpose, where you have full control.

-Steve
Jan 04 2018
prev sibling parent =?UTF-8?Q?Ali_=c3=87ehreli?= <acehreli yahoo.com> writes:
On 01/04/2018 11:16 AM, Marc wrote:

 For code generation purposes, I'd like to pass a type name to base 
 class. I'm not sure if it's supported, I didn't find anything at 
 documentation for class constructor but it does compile:
 

 class A {
     static {
         int a, b;
     }

     this(T)() {

     }
 }


 
 then do something like this:
 

 class B {
  this() {
    super!B;
  }
 }


 
 but I got the error:
 

 found ! when expecting ; following statement




Checkout the "this template parameter":

class A {
     static {
         int a, b;
     }

     this(this T)() {
         import std.stdio;
         writeln(T.stringof);
     }
}

class B : A {
     this() {
         super();
     }
}

void main() {
     auto b = new B();
}

Ali
Jan 04 2018