make a new package for helpers

2022-07-27 22:42:35 -05:00
parent 0df45acba3
commit 831bf9ea44
35 changed files with 276 additions and 49 deletions
--- a/packages/helpers/is-instance-of.ts
+++ b/packages/helpers/is-instance-of.ts
@@ -0,0 +1,7 @@
+/**
+ * for narrowing instance types with array.filter
+ */
+export const isInstanceOf =
+  <T>(Constructor: new (...args: any[]) => T) =>
+  (value: unknown): value is T =>
+    value instanceof Constructor