[llvm] r242823 - Add some utilities to iterator_range for trimming a range and constructing one from a container.

[Justin Bogner via llvm-commits]

David Blaikie <dblaikie at gmail.com> writes:
> Author: dblaikie
> Date: Tue Jul 21 13:37:12 2015
> New Revision: 242823
>
> URL: http://llvm.org/viewvc/llvm-project?rev=242823&view=rev
> Log:
> Add some utilities to iterator_range for trimming a range and
> constructing one from a container.
>
> To be used in clang in a follow-up commit.
>
> Modified:
>     llvm/trunk/include/llvm/ADT/iterator_range.h
>
> Modified: llvm/trunk/include/llvm/ADT/iterator_range.h
> URL:
> http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/ADT/iterator_range.h?rev=242823&r1=242822&r2=242823&view=diff
> ==============================================================================
>
> --- llvm/trunk/include/llvm/ADT/iterator_range.h (original)
> +++ llvm/trunk/include/llvm/ADT/iterator_range.h Tue Jul 21 13:37:12 2015
> @@ -20,6 +20,7 @@
>  #define LLVM_ADT_ITERATOR_RANGE_H
>  
>  #include <utility>
> +#include <iterator>
>  
>  namespace llvm {
>  
> @@ -32,6 +33,12 @@ class iterator_range {
>    IteratorT begin_iterator, end_iterator;
>  
>  public:
> +  //TODO: Add SFINAE to test that the Container's iterators match the range's
> +  //      iterators.
> +  template <typename Container>
> +  iterator_range(Container &&c)
> +  //TODO: Consider ADL/non-member begin/end calls.
> +      : begin_iterator(c.begin()), end_iterator(c.end()) {}
>    iterator_range(IteratorT begin_iterator, IteratorT end_iterator)
>        : begin_iterator(std::move(begin_iterator)),
>          end_iterator(std::move(end_iterator)) {}
> @@ -51,6 +58,11 @@ template <class T> iterator_range<T> mak
>  template <typename T> iterator_range<T> make_range(std::pair<T, T> p) {
>    return iterator_range<T>(std::move(p.first), std::move(p.second));
>  }
> +
> +template<typename T>
> +iterator_range<decltype(begin(std::declval<T>()))> drop_begin(T &&t, int n) {
> +  return make_range(std::next(begin(t), n), end(t));

Sorry for the commit necromancy, but should these be std::begin and
std::end, or perhaps have locally scoped using directives? As is this
doesn't seem to work for llvm:: types like SmallVector.

> +}
>  }
>  
>  #endif
>
>
> _______________________________________________
> llvm-commits mailing list
> llvm-commits at cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits