Add unwrap function to option module

2 files changed, 25 insertions, 0 deletions

diff --git a/src/gleam/option.gleam b/src/gleam/option.gleam
index e5be4cc..663cd1f 100644
--- a/src/gleam/option.gleam
+++ b/src/gleam/option.gleam
@@ -68,3 +68,20 @@ pub fn from_result(result: Result(a, e)) -> Option(a) {
     _ -> None
   }
 }
+
+/// Extract the value from an option, returning a default value if there is none.
+///
+/// ## Examples
+///
+///    > unwrap(Some(1), 0)
+///    1
+///
+///    > unwrap(None, 0)
+///    0
+///
+pub fn unwrap(option: Option(a), or default: a) -> a {
+  case option {
+    Some(x) -> x
+    None -> default
+  }
+}
diff --git a/test/gleam/option_test.gleam b/test/gleam/option_test.gleam
index a6f2cc3..e41c221 100644
--- a/test/gleam/option_test.gleam
+++ b/test/gleam/option_test.gleam
@@ -32,3 +32,11 @@ pub fn from_result_test() {
   option.from_result(Error("some_error"))
   |> should.equal(None)
 }
+
+pub fn unwrap_option_test() {
+  option.unwrap(Some(1), 0)
+  |> should.equal(1)
+
+  option.unwrap(None, 0)
+  |> should.equal(0)
+}