diff options
| -rw-r--r-- | src/gleam/float.gleam | 19 | ||||
| -rw-r--r-- | test/gleam/float_test.gleam | 8 |
2 files changed, 27 insertions, 0 deletions
diff --git a/src/gleam/float.gleam b/src/gleam/float.gleam index 24f0330..3d611b5 100644 --- a/src/gleam/float.gleam +++ b/src/gleam/float.gleam @@ -171,3 +171,22 @@ pub fn square_root(number: Float) -> Result(Float, Nil) { pub fn negate(x: Float) -> Float { -1. *. x } + +/// Sums a list of Floats. +/// +/// ## Example +/// +/// > sum([1.0, 2.2, 3.3]) +/// 6.5 +/// +pub fn sum(numbers: List(Float)) -> Float { + numbers + |> do_sum(0.0) +} + +fn do_sum(numbers: List(Float), initial: Float) -> Float { + case numbers { + [] -> initial + [x, ..rest] -> do_sum(rest, x +. initial) + } +} diff --git a/test/gleam/float_test.gleam b/test/gleam/float_test.gleam index be1f22d..2ebaefc 100644 --- a/test/gleam/float_test.gleam +++ b/test/gleam/float_test.gleam @@ -242,3 +242,11 @@ pub fn negate_test() { float.negate(0.) |> should.equal(0.) } + +pub fn sum_test() { + float.sum([]) + |> should.equal(0.0) + + float.sum([1.0, 2.2, 3.3]) + |> should.equal(6.5) +} |