string.to_graphemes

3 files changed, 28 insertions, 10 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index e4d91dd..e424e0c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,8 +5,8 @@
 - Created the `io` module with `print` function.
 - The `result` module gains the `nil_error` function.
 - The `string` module gains `trim`, `trim_left`, `trim_right`, `starts_with`,
-  `ends_with`, `slice`, `pad_left`, `pad_right` `drop_left`, `drop_right` and
-  `pop_grapheme` functions.
+  `ends_with`, `slice`, `pad_left`, `pad_right` `drop_left`, `drop_right`,
+  `pop_grapheme` and `to_graphemes' functions.
 - `uri` module created with `parse`, `parse_query`, `path_segments`,
   `query_to_string` and `to_string`.
 - The `dynamic` module gains the `map`, `opaque_list`, `tuple2`, and `tuple2_of` functions.
diff --git a/src/gleam/string.gleam b/src/gleam/string.gleam
index cf2a585..a6c7944 100644
--- a/src/gleam/string.gleam
+++ b/src/gleam/string.gleam
@@ -400,14 +400,6 @@ pub fn trim_right(string: String) -> String {
   erl_trim(string, Trailing)
 }
 
-// TODO
-// /// Convert a string to a list of Graphemes.
-// ///
-// ///    > to_graphemes("abc")
-//    ['a','b','c']
-//
-// ///
-// pub fn to_graphemes(string: String) -> List(String) {}
 /// Split a non-empty string into its head and tail. This lets you
 /// pattern match on strings exactly as you would with lists.
 ///
@@ -420,3 +412,15 @@ pub fn trim_right(string: String) -> String {
 ///
 pub external fn pop_grapheme(string: String) -> Option(tuple(String, String)) =
   "gleam_stdlib" "string_pop_grapheme"
+
+/// Convert a string to a list of Graphemes.
+///
+///    > to_graphemes("abc")
+///    ["a", "b", "c"]
+///
+pub fn to_graphemes(string: String) -> List(String) {
+  case pop_grapheme(string) {
+    Ok(tuple(grapheme, rest)) -> [grapheme, ..to_graphemes(rest)]
+    _ -> []
+  }
+}
diff --git a/test/gleam/string_test.gleam b/test/gleam/string_test.gleam
index c8eae63..2fbb84f 100644
--- a/test/gleam/string_test.gleam
+++ b/test/gleam/string_test.gleam
@@ -267,3 +267,17 @@ pub fn pop_grapheme_test() {
   |> string.pop_grapheme()
   |> should.equal(Error(Nil))
 }
+
+pub fn to_graphemes_test() {
+  "abc"
+  |> string.to_graphemes()
+  |> should.equal(["a", "b", "c"])
+
+  "a"
+  |> string.to_graphemes()
+  |> should.equal(["a"])
+
+  ""
+  |> string.to_graphemes()
+  |> should.equal([])
+}