diff options
| -rw-r--r-- | src/gleam/list.gleam | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/src/gleam/list.gleam b/src/gleam/list.gleam index 422f26b..f2f3e5f 100644 --- a/src/gleam/list.gleam +++ b/src/gleam/list.gleam @@ -748,6 +748,13 @@ pub fn unzip(input: List(tuple(a, b))) -> tuple(List(a), List(b)) { do_unzip(input, [], []) } +fn do_intersperse(list: List(a), separator: a, acc: List(a)) -> List(a) { + case list { + [] -> reverse(acc) + [x, ..rest] -> do_intersperse(rest, separator, [x, separator, ..acc]) + } +} + /// Inserts a given value between each existing element in a given list. /// /// This function runs in linear time and copies the list. @@ -763,7 +770,7 @@ pub fn unzip(input: List(tuple(a, b))) -> tuple(List(a), List(b)) { pub fn intersperse(list: List(a), with elem: a) -> List(a) { case list { [] | [_] -> list - [x, ..rest] -> [x, elem, ..intersperse(rest, elem)] + [x, ..rest] -> do_intersperse(rest, elem, [x]) } } |