diff options
| -rw-r--r-- | src/gleam/dict.gleam | 18 | ||||
| -rw-r--r-- | test/gleam/dict_test.gleam | 17 |
2 files changed, 35 insertions, 0 deletions
diff --git a/src/gleam/dict.gleam b/src/gleam/dict.gleam index f44daa3..99ca30c 100644 --- a/src/gleam/dict.gleam +++ b/src/gleam/dict.gleam @@ -35,6 +35,24 @@ pub type Dict(key, value) @external(javascript, "../gleam_stdlib.mjs", "map_size") pub fn size(dict: Dict(k, v)) -> Int +/// Determines whether or not the dict is empty. +/// +/// ## Examples +/// +/// ```gleam +/// new() |> is_empty +/// // -> True +/// ``` +/// +/// ```gleam +/// new() |> insert("b", 1) |> is_empty +/// // -> False +/// ``` +/// +pub fn is_empty(dict: Dict(a, b)) -> Bool { + dict == new() +} + /// Converts the dict to a list of 2-element tuples `#(key, value)`, one for /// each key-value pair in the dict. /// diff --git a/test/gleam/dict_test.gleam b/test/gleam/dict_test.gleam index 0bcb334..9ec1475 100644 --- a/test/gleam/dict_test.gleam +++ b/test/gleam/dict_test.gleam @@ -349,6 +349,23 @@ pub fn size_test() { |> should.equal(18) } +pub fn is_empty_test() { + dict.new() + |> dict.is_empty() + |> should.be_true() + + dict.new() + |> dict.insert(1, 10) + |> dict.is_empty() + |> should.be_false() + + dict.new() + |> dict.insert(1, 10) + |> dict.delete(1) + |> dict.is_empty() + |> should.be_true() +} + // https://github.com/gleam-lang/stdlib/issues/435 pub fn peters_bug_test() { dict.new() |