cpp/ranges/drop view

@1@ A range adaptor consisting of elements of the underlying sequence, skipping the first N elements.

@2@ . Given is  and  is ), the expression  is expression-equivalent to:


 * , if is a, except that the evaluations of  and  are indeterminately sequenced;
 * otherwise,, if is a specialization of  that models both  and , and  needs to store the size (see  for details), where  is ;
 * otherwise,, if is a specialization of , std, , or  that models both  and , where  is
 * , if is a specialization of ;
 * otherwise;


 * otherwise,.

In all cases, must model.

models the concepts, , , , , , and when the underlying view  models respective concepts.

Helper templates
This specialization of makes  satisfy  when the underlying view satisfies it.