Add span::ssize(), size(nonstd::span), ssize(nonstd::span) (#27)

include/nonstd/span.hpp

@@ -913,6 +913,11 @@ class span
         return size_;
     }
 
+    span_constexpr std::ptrdiff_t ssize() const span_noexcept
+    {
+        return static_cast<std::ptrdiff_t>( size_ );
+    }
+
     span_constexpr index_type size_bytes() const span_noexcept
     {
         return size() * to_size( sizeof( element_type ) );
@@ -1210,6 +1215,20 @@ subspan( T & t, index_t offset, extent_t count = dynamic_extent ) -> decltype( m
 
 #endif // span_FEATURE( NON_MEMBER_FIRST_LAST_SUB )
 
+// 27.8 Container and view access [iterator.container]
+
+template< class T, extent_t Extent /*= dynamic_extent*/ >
+span_constexpr std::size_t size( span<T,Extent> const & spn )
+{
+    return static_cast<std::size_t>( spn.size() );
+}
+
+template< class T, extent_t Extent /*= dynamic_extent*/ >
+span_constexpr std::ptrdiff_t ssize( span<T,Extent> const & spn )
+{
+    return static_cast<std::ptrdiff_t>( spn.size() );
+}
+
 }  // namespace span_lite
 }  // namespace nonstd
 
@@ -1238,6 +1257,10 @@ using span_lite::as_writeable_bytes;
 #if span_FEATURE( SAME )
 using span_lite::same;
 #endif
+
+using span_lite::size;
+using span_lite::ssize;
+
 }  // namespace nonstd
 
 #endif  // span_USES_STD_SPAN

test/span.t.cpp

@@ -973,6 +973,20 @@ CASE( "span<>: Allows to obtain the number of elements via size()" )
     EXPECT(  z.size() == index_type( 0 ) );
 }
 
+CASE( "span<>: Allows to obtain the number of elements via ssize()" )
+{
+    int a[] = { 1, 2, 3, };
+    int b[] = { 1, 2, 3, 4, 5, };
+
+    span<int> z;
+    span<int> va( a );
+    span<int> vb( b );
+
+    EXPECT( va.ssize() == DIMENSION_OF( a ) );
+    EXPECT( vb.ssize() == DIMENSION_OF( b ) );
+    EXPECT(  z.ssize() == 0 );
+}
+
 CASE( "span<>: Allows to obtain the number of bytes via size_bytes()" )
 {
     int a[] = { 1, 2, 3, };
@@ -1390,6 +1404,34 @@ CASE( "subspan(): Allows to create a sub span starting at a given offset" )
 #endif
 }
 
+CASE( "size(): Allows to obtain the number of elements via size()" )
+{
+    int a[] = { 1, 2, 3, };
+    int b[] = { 1, 2, 3, 4, 5, };
+
+    span<int> z;
+    span<int> va( a );
+    span<int> vb( b );
+
+    EXPECT( size( va ) == index_type( DIMENSION_OF( a ) ) );
+    EXPECT( size( vb ) == index_type( DIMENSION_OF( b ) ) );
+    EXPECT( size( z  ) == index_type( 0 ) );
+}
+
+CASE( "ssize(): Allows to obtain the number of elements via ssize()" )
+{
+    int a[] = { 1, 2, 3, };
+    int b[] = { 1, 2, 3, 4, 5, };
+
+    span<int> z;
+    span<int> va( a );
+    span<int> vb( b );
+
+    EXPECT( ssize( va ) == DIMENSION_OF( a ) );
+    EXPECT( ssize( vb ) == DIMENSION_OF( b ) );
+    EXPECT( ssize( z  ) == 0 );
+}
+
 // Issues
 
 #include <cassert>