implements 0.14.0

Macro to answer the question: does it implement a trait?
Documentation 
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#[ doc( hidden ) ]
#[ macro_export ]
macro_rules! _implements
{
  ( $V: expr => $( $Traits: tt )+ ) =>
  {{
  use ::core ::marker ::PhantomData;

  trait False
  {
   fn get( self: &'_ Self ) -> bool { false }
 }

  impl< T > False
  for &'_ PhantomData< T >
  where T: ?Sized,
  {}

  trait True
  {
   fn get( self: &'_ Self ) -> bool { true }
 }

  impl< T > True
  for PhantomData< T >
  where T: $( $Traits )+ + ?Sized,
  {}

  fn does< T: Sized >( _: &T ) -> PhantomData< T >
  {
   PhantomData
 }
  ( &does( &$V ) ).get()

 }};
}