monocle-ts - npm Package Compare versions

Comparing version 0.4.3 to 0.4.4

CHANGELOG.md

@@ -15,2 +15,7 @@ # Changelog
 
+# 0.4.4
+
+- **New Feature**
+  - add `Lens.fromNullableProp` (@gcanti)
+
 # 0.4.3
@@ -17,0 +22,0 @@

lib/index.d.ts

@@ -69,2 +69,4 @@ import { HKT, HKTS, HKTAs, HKT2S, HKT2As } from 'fp-ts/lib/HKT';
     static fromProp<T, P extends keyof T>(prop: P): Lens<T, T[P]>;
+    /** generate a lens from a type and a prop whose type is nullable */
+    static fromNullableProp<S, A extends S[K], K extends keyof S>(k: K, defaultValue: A): Lens<S, A>;
     modify(f: (a: A) => A): (s: S) => S;
@@ -71,0 +73,0 @@ /** view a Lens as a Optional */

lib/index.js

@@ -132,2 +132,9 @@ "use strict";
     };
+    /** generate a lens from a type and a prop whose type is nullable */
+    Lens.fromNullableProp = function (k, defaultValue) {
+        return new Lens(function (s) { return Option_1.fromNullable(s[k]).getOrElseValue(defaultValue); }, function (a) { return function (s) {
+            return (__assign({}, s, (_a = {}, _a[k] = a, _a)));
+            var _a;
+        }; });
+    };
     Lens.prototype.modify = function (f) {
@@ -134,0 +141,0 @@ var _this = this;

package.json

 {
   "name": "monocle-ts",
-  "version": "0.4.3",
+  "version": "0.4.4",
   "description": "A porting of scala monocle library to TypeScript",
@@ -5,0 +5,0 @@ "files": ["lib"],

README.md

@@ -129,2 +129,3 @@ # Motivation
   - [fromProp](#fromprop)
+  - [fromNullableProp](#fromnullableprop)
   - [Methods](#methods-1)
@@ -165,3 +166,3 @@ - [modify](#modify-1)
 - [Optional](#optional)
-  - [fromNullableProp](#fromnullableprop)
+  - [fromNullableProp](#fromnullableprop-1)
   - [Methods](#methods-3)
@@ -441,2 +442,4 @@ - [modify](#modify-3)
 
+generate a lens from a type and a prop
+
 Example
@@ -458,2 +461,32 @@
 
+## fromNullableProp
+
+```ts
+<S, A extends S[K], K extends keyof S>(k: K, defaultValue: A): Lens<S, A>
+```
+
+generate a lens from a type and a prop whose type is nullable
+
+Example
+
+```ts
+interface Outer {
+  inner?: Inner
+}
+
+interface Inner {
+  value: number
+  foo: string
+}
+
+const inner = Lens.fromNullableProp<Outer, Inner, 'inner'>('inner', { value: 0, foo: 'foo' })
+const value = Lens.fromProp<Inner, 'value'>('value')
+const lens = inner.compose(value)
+
+console.log(lens.set(1)({})) // { inner: { value: 1, foo: 'foo' } }
+console.log(lens.get({})) // 0
+console.log(lens.set(1)({ inner: { value: 1, foo: 'bar' } })) // { inner: { value: 1, foo: 'bar' } }
+console.log(lens.get({ inner: { value: 1, foo: 'bar' } })) // 1
+```
+
 ## Methods
@@ -460,0 +493,0 @@

No alert changes

Improved metrics

Total package byte prevSize

82635

increased by2.14%

Lines of code

862

increased by1.06%

Number of lines in readme file

1261

increased by2.69%

No dependency changes