composable-functions - npm Package Compare versions

Comparing version 1.0.0-beta-20240523-2 to 1.0.0-beta-20240523-3

package.json

 {
   "name": "composable-functions",
-  "version": "1.0.0-beta-20240523-2",
+  "version": "1.0.0-beta-20240523-3",
   "description": "Types and functions to make composition easy and safe",
@@ -5,0 +5,0 @@ "author": "Seasoned",

README.md

@@ -163,2 +163,25 @@ <p align="center">
 
+You can throw anything derived from `Error`. Check [this documentation](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error#custom_error_types) on how to define your custom errors. The library will also wrap anything that does not extends `Error`, just to keep compatibility with code-bases that throw strings or objects.
+
+```typescript
+import { composable } from 'composable-functions'
+
+class NotFoundError extends Error {
+  constructor(message) {
+    super(message);
+    this.name = 'NotFoundError';
+  }
+}
+
+const getUser = composable((userId: string, users: Array<string>) => {
+//    ^? Composable<(userId: string, users: Array<string>) => string>
+    const result = users.find(({id}) => id === userId)
+    if(result == undefined) throw new NotFoundError(`userId ${userId} was not found`)
+    return result
+})
+```
+
+The library defines a few custom errors out of the box but these will be more important later on, whend dealing with external input and schemas.
+See [the errors module](./src/errors.ts) for more details.
+
 ### Catching
@@ -170,4 +193,3 @@ You can catch an error in a `Composable`, using `catchFailure` which is similar to `map` but will run whenever the first composable fails:
 
-const getUser = composable((id: string) => fetchUser(id))
-//    ^? Composable<(id: string) => User>
+// assuming we have the definitions from the previous example
 const getOptionalUser = catchFailure(getUser, (errors, id) => {
@@ -177,3 +199,3 @@ console.log(`Failed to fetch user with id ${id}`, errors)
 })
-//    ^? Composable<(id: string) => User | null>
+//    ^? Composable<(id: string) => string | null>
 ```
@@ -180,0 +202,0 @@

No alert changes

Improved metrics

Total package byte prevSize

153564

increased by46.17%

Number of package files

42

increased by10.53%

Number of lines in readme file

274

increased by8.73%

No dependency changes