Promise rescue

2 files changed, 9 insertions, 0 deletions

diff --git a/src/ffi.js b/src/ffi.js
index 450f5e3..d3ee8ce 100644
--- a/src/ffi.js
+++ b/src/ffi.js
@@ -94,3 +94,7 @@ export function map_promise(promise, fn) {
     PromiseLayer.wrap(fn(PromiseLayer.unwrap(value)))
   );
 }
+
+export function rescue(promise, fn) {
+  return promise.catch((error) => fn(error));
+}
diff --git a/src/gleam/javascript/promise.gleam b/src/gleam/javascript/promise.gleam
index 8407c8c..3c7190c 100644
--- a/src/gleam/javascript/promise.gleam
+++ b/src/gleam/javascript/promise.gleam
@@ -1,3 +1,5 @@
+import gleam/dynamic.{Dynamic}
+
 // TODO: docs
 // TODO: labels
 pub external type Promise(value)
@@ -5,6 +7,9 @@ pub external type Promise(value)
 pub external fn resolve(value) -> Promise(value) =
   "../../ffi.js" "resolve"
 
+pub external fn rescue(Promise(value), fn(Dynamic) -> value) -> Promise(value) =
+  "../../ffi.js" "rescue"
+
 pub external fn then(Promise(a), fn(a) -> Promise(b)) -> Promise(b) =
   "../../ffi.js" "then"