Add core:encoding/endian

core/encoding/endian/doc.odin

@@ -0,0 +1,23 @@
+/*
+    Package endian implements sa simple translation between bytes and numbers with
+    specific endian encodings.
+
+    buf: [100]u8
+    put_u16(buf[:], .Little, 16) or_return
+
+    You may ask yourself, why isn't `byte_order` platform Endianness by default, so we can write:
+    put_u16(buf[:], 16) or_return
+
+    The answer is that very few file formats are written in native/platform endianness. Most of them specify the endianness of
+    each of their fields, or use a header field which specifies it for the entire file.
+
+    e.g. a file which specifies it at the top for all fields could do this:
+    file_order := .Little if buf[0] == 0 else .Big
+    field := get_u16(buf[1:], file_order) or_return
+
+    If on the other hand a field is *always* Big-Endian, you're wise to explicitly state it for the benefit of the reader,
+    be that your future self or someone else.
+
+    field := get_u16(buf[:], .Big) or_return
+*/
+package encoding_endian