1 files changed, 78 insertions, 0 deletions
diff --git a/src/include/stdspan.hpp b/src/include/stdspan.hpp
new file mode 100644
index 00000000..0d574cfc
--- /dev/null
+++ b/src/include/stdspan.hpp
@@ -0,0 +1,78 @@
+/*
+ * MRustC - Mutabah's Rust Compiler
+ * - By John Hodge (Mutabah/thePowersGang)
+ *
+ * include/stdspan.hpp
+ * - Clone of the C++20 span class
+ */
+#pragma once
+#include <vector>
+#include <iostream> // ostream
+
+namespace std {
+
+template<typename T>
+class span
+{
+    T*  m_first;
+    unsigned int    m_len;
+public:
+    span():
+        m_first(nullptr),
+        m_len(0)
+    {}
+    span(const ::std::vector<T>& v):
+        m_first(&v[0]),
+        m_len(v.size())
+    {}
+    span(::std::vector<T>& v):
+        m_first(&v[0]),
+        m_len(v.size())
+    {}
+    span(T* ptr, unsigned int len):
+        m_first(ptr),
+        m_len(len)
+    {}
+
+    ::std::vector<T> to_vec() const {
+        return ::std::vector<T>(begin(), end());
+    }
+
+    unsigned int size() const {
+        return m_len;
+    }
+    T& operator[](unsigned int i) const {
+        assert(i < m_len);
+        return m_first[i];
+    }
+    span<T> subspan(unsigned int ofs, unsigned int len) const {
+        assert(ofs < m_len);
+        assert(len <= m_len);
+        assert(ofs + len <= m_len);
+        return span { m_first + ofs, len };
+    }
+
+    T* begin() const { return m_first; }
+    T* end() const { return m_first + m_len; }
+
+    T& front() const { return m_first[0]; }
+    T& back() const { return m_first[m_len-1]; }
+};
+
+template<typename T>
+::std::ostream& operator<<(::std::ostream& os, span<T> s) {
+    if( s.size() > 0 )
+    {
+        bool is_first = true;
+        for( const auto& i : s )
+        {
+            if(!is_first)
+                os << ", ";
+            is_first = false;
+            os << i;
+        }
+    }
+    return os;
+}
+
+}