Add casting function for coral::fixed_buffer to coral::slice

source/coral/io.cpp

@@ -10,6 +10,16 @@ export namespace coral {
 	template<usize capacity> struct fixed_buffer : public writer, public reader {
 		fixed_buffer(coral::u8 fill_value) : data{fill_value} {}
 
+		/**
+		 * Returns a mutable [slice] ranging from the head to the last-filled element.
+		 *
+		 * *Note*: The lifetime and validity of the returned slice is only guaranteed for as long
+		 * as the source [fixed_buffer] is not mutated or out-of-scope.
+		 */
+		slice<u8 const> as_slice() const {
+			return {0, this->filled};
+		}
+
 		/**
 		 * Returns the base pointer of the buffer data.
 		 */