Type-generic expression

 

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Implements a form of type-polymorphism mechanism.

Syntax

_Generic ( assignment-expression , type-name1 : assignment-expression1 , type-name2 : assignment-expression2 , ... ... ... type-namen : assignment-expressionn , default: assignment-expression (optional) )

Explanation

The first assignment-expression is the controlling expression and determines the result of the generic selection. If the type of the controlling expression is compatible with one of the type-name_i, then the result of the generic selection is the value of the assignment-expression_i in the generic association. Otherwise, the result expression of the generic selection is the expression in the default generic association. If a generic selection has no default generic association, then the type of the controlling expression must be compatible with exactly one of the types named in its generic association list.

Keywords

_Generic, default

Example

Run this code

#include <stdio.h>
 
int main(void)
{
    printf("%d\n",_Generic( 1.0L, float:1, double:2, long double:3, default:0));
    printf("%d\n",_Generic( 1L, float:1, double:2, long double:3, default:0));
    printf("%d\n",_Generic( 1.0L, float:1, double:2, long double:3));
}

Possible output:

3
0
3