Initial data commit

Task/UTF-8-encode-and-decode/Lua/utf-8-encode-and-decode.lua

@@ -0,0 +1,34 @@
+-- Accept an integer representing a codepoint.
+-- Return the values of the individual octets.
+function encode (codepoint)
+  local codepoint_str = utf8.char(codepoint)
+  local result = {}
+
+  for i = 1, #codepoint_str do
+    result[#result + 1] = string.unpack("B", codepoint_str, i)
+  end
+
+  return table.unpack(result)
+end
+
+-- Accept a variable number of octets.
+-- Return the corresponding Unicode character.
+function decode (...)
+  local len = select("#", ...) -- the number of octets
+  local fmt = string.rep("B", len)
+
+  return string.pack(fmt, ...)
+end
+
+-- Run the given test cases.
+function test_encode_decode ()
+  -- "A", "ö", "Ж", "€", "𝄞"
+  local tests = {tonumber("41", 16),  tonumber("f6", 16), tonumber("416", 16),
+                  tonumber("20ac", 16), tonumber("1d11e", 16)}
+
+  for i, test in ipairs(tests) do
+    print("Char: ", test)
+    print("Encoding: ", encode(test))
+    print("Decoding: ", decode(encode(test)))
+  end
+end