BLI: add index_range method to some data structures

This can be used to iterate over all indices with less code.

source/blender/blenlib/BLI_allocator.h

@@ -30,6 +30,7 @@
  */
 
 #include <stdlib.h>
+#include <algorithm>
 
 #include "MEM_guardedalloc.h"
 

source/blender/blenlib/BLI_array_cxx.h

@@ -27,6 +27,7 @@
 #include "BLI_allocator.h"
 #include "BLI_array_ref.h"
 #include "BLI_memory_utils_cxx.h"
+#include "BLI_index_range.h"
 
 namespace BLI {
 
@@ -182,6 +183,11 @@ template<typename T, typename Allocator = GuardedAllocator> class Array {
     return m_data + m_size;
   }
 
+  IndexRange index_range() const
+  {
+    return IndexRange(m_size);
+  }
+
  private:
   T *allocate(uint size)
   {

source/blender/blenlib/BLI_array_ref.h

@@ -246,6 +246,11 @@ template<typename T> class ArrayRef {
     return fallback;
   }
 
+  IndexRange index_range() const
+  {
+    return IndexRange(m_size);
+  }
+
   /**
    * Get a new array ref to the same underlying memory buffer. No conversions are done.
    * Asserts when the sizes of the types don't match.
@@ -411,6 +416,11 @@ template<typename T> class MutableArrayRef {
   {
     return ArrayRef<T>(m_start, m_size);
   }
+
+  IndexRange index_range() const
+  {
+    return IndexRange(m_size);
+  }
 };
 
 /**

source/blender/blenlib/BLI_vector.h

@@ -37,6 +37,7 @@
 #include "BLI_listbase_wrapper.h"
 #include "BLI_math_base.h"
 #include "BLI_allocator.h"
+#include "BLI_index_range.h"
 
 #include "MEM_guardedalloc.h"
 
@@ -520,6 +521,11 @@ template<typename T, uint N = 4, typename Allocator = GuardedAllocator> class Ve
     return (uint)(m_capacity_end - m_begin);
   }
 
+  IndexRange index_range() const
+  {
+    return IndexRange(this->size());
+  }
+
   void print_stats() const
   {
     std::cout << "Small Vector at " << (void *)this << ":" << std::endl;