According to wiki, sequence is a better name

src/morsey.gleam

@@ -20,7 +20,7 @@ pub type Char {
   Invalid(String)
 }
 
-pub type Code =
+pub type Sequence =
   List(Char)
 
 pub type EncodeError {
@@ -38,15 +38,15 @@ pub fn main() {
   }
 }
 
-pub fn encode(text: String) -> Result(Code, EncodeError) {
+pub fn encode(text: String) -> Result(Sequence, EncodeError) {
   let encoded = encode_sentence(text)
   case first_invalid_character(encoded) {
     Ok(char) -> Error(InvalidCharacter(char))
     Error(Nil) -> Ok(encoded)
   }
 }
 
-pub fn to_string(encoded: Code) -> String {
+pub fn to_string(encoded: Sequence) -> String {
   encoded
   |> list.map(fn(symbol) {
     case symbol {
@@ -60,7 +60,7 @@ pub fn to_string(encoded: Code) -> String {
   |> string.join("")
 }
 
-pub fn from_string(text: String) -> Code {
+pub fn from_string(text: String) -> Sequence {
   text
   |> string.to_graphemes
   |> list.map(fn(x) {
@@ -111,7 +111,7 @@ fn first_invalid_character(symbols) -> Result(String, Nil) {
   |> list.first
 }
 
-fn encode_char(char: String) -> Code {
+fn encode_char(char: String) -> Sequence {
   let char = string.uppercase(char)
   let encode_map = dict.from_list(map())
   case encode_map |> dict.get(char) {
@@ -120,7 +120,7 @@ fn encode_char(char: String) -> Code {
   }
 }
 
-fn encode_word(word: String) -> Code {
+fn encode_word(word: String) -> Sequence {
   let encoded =
     string.to_graphemes(word)
     |> list.map(encode_char)
@@ -129,7 +129,7 @@ fn encode_word(word: String) -> Code {
   list.take(encoded, list.length(encoded) - 1)
 }
 
-fn encode_sentence(sentence: String) -> Code {
+fn encode_sentence(sentence: String) -> Sequence {
   let encoded =
     sentence
     |> string.split(" ")