Derive Macro Index 

#[derive(Index)]
{
    // Attributes available to this derive:
    #[index]
}

Implement Index for a structure.

Sample.

use derive_tools::Index;

#[ derive( Index ) ]
struct MyStruct( i32 );

let my_struct = MyStruct( 13 );
dbg!( my_struct[ 0 ] );

To learn more about the feature, study the module derive_tools::Index.