immutable-lens - npm Package Compare versions

Comparing version 0.0.1 to 0.0.2

lib/Lens.d.ts

@@ -0,10 +1,15 @@
+export interface NotAnArray {
+    reduceRight?: 'NotAnArray';
+}
 export interface ValueUpdater<V> {
     (value: V): V;
 }
-export declare type FieldsUpdater<T> = object & {
-    [K in keyof T]?: T[K] | ValueUpdater<T[K]>;
+export declare type FieldValues<T> = object & NotAnArray & {
+    [K in keyof T]?: T[K];
 };
+export declare type FieldUpdaters<T> = object & NotAnArray & {
+    [K in keyof T]?: ValueUpdater<T[K]>;
+};
 export interface Lens<T, Target> {
-    focusOn<TO extends T & object, K extends keyof Target>(this: Lens<TO, Target>, key: K): Lens<T, Target[K]>;
-    focusAt<NewTarget>(lens: Lens<Target, NewTarget>): Lens<T, NewTarget>;
+    focusOn<K extends keyof Target>(this: Lens<T, Target & NotAnArray>, key: K): Lens<T, Target[K]>;
     focusIndex<Item>(this: Lens<T, Item[]>, index: number): Lens<T, Item | undefined>;
@@ -14,5 +19,9 @@ read(source: T): Target;
     update(source: T, updater: ValueUpdater<Target>): T;
-    updateFields(this: Lens<T, Target & object>, source: T, fields: FieldsUpdater<Target>): T;
+    setFieldValues(this: Lens<T, Target & NotAnArray>, source: T, fields: FieldValues<Target>): T;
+    updateFields(this: Lens<T, Target & NotAnArray>, source: T, updaters: FieldUpdaters<Target>): T;
+    getPath(): string;
+    defaultTo<SafeTarget extends Target>(this: Lens<T, SafeTarget | undefined>, value: SafeTarget): Lens<T, SafeTarget>;
 }
-export declare type UnfocusedLens<T> = Lens<T, T>;
-export declare function createLens<T extends object>(sample?: T): UnfocusedLens<T>;
+export interface UnfocusedLens<T> extends Lens<T, T> {
+}
+export declare function createLens<T extends object>(instance?: T): UnfocusedLens<T>;

lib/Lens.js

 "use strict";
-var __assign = (this && this.__assign) || Object.assign || function(t) {
-    for (var s, i = 1, n = arguments.length; i < n; i++) {
-        s = arguments[i];
-        for (var p in s) if (Object.prototype.hasOwnProperty.call(s, p))
-            t[p] = s[p];
-    }
-    return t;
-};
 Object.defineProperty(exports, "__esModule", { value: true });
-function createLens(sample) {
-    return {
-        focusOn: function (key) {
-            return focusLens(this, key);
-        },
-        read: function (source) {
-            return source;
-        },
-        setValue: function (source, newValue) {
-            return newValue;
-        },
-        update: function (source, updater) {
-            return updater(source);
-        },
-        updateFields: function (source, fields) {
-            return updateFields(source, fields);
-        }
-    };
+var RootLens_1 = require("./RootLens");
+function createLens(instance) {
+    return new RootLens_1.RootLens();
 }
 exports.createLens = createLens;
-function focusLens(parentLens, key) {
-    return {
-        read: function (source) {
-            return parentLens.read(source)[key];
-        },
-        setValue: function (source, newValue) {
-            var fields = {};
-            fields[key] = newValue;
-            return parentLens.updateFields(source, fields);
-        },
-        update: function (source, updater) {
-            var fields = {};
-            fields[key] = updater;
-            return parentLens.updateFields(source, fields);
-        },
-        updateFields: function (source, fields) {
-            var updatedFields = updateFields(this.read(source), fields);
-            return this.setValue(source, updatedFields);
-        }
-    };
-}
-function updateFields(source, fields) {
-    if (typeof fields === 'function')
-        throw Error('Lens.updateFields() does NOT accept functions as argument');
-    var hasChanged = false;
-    var sourceObject = source;
-    var fieldsObject = fields;
-    if (Object.keys(fields).length === 0)
-        return source;
-    var copy = __assign({}, sourceObject);
-    for (var key in fields) {
-        var fieldSpec = fieldsObject[key];
-        if (typeof fieldSpec === 'function') {
-            var newValue = fieldSpec(sourceObject[key]);
-            if (newValue !== sourceObject[key]) {
-                hasChanged = true;
-                copy[key] = newValue;
-            }
-        }
-        else {
-            var newValue = fieldSpec;
-            if (newValue !== sourceObject[key]) {
-                copy[key] = fieldSpec;
-                hasChanged = true;
-            }
-        }
-    }
-    return hasChanged ? copy : source;
-}
 //# sourceMappingURL=Lens.js.map

package.json

 {
   "name": "immutable-lens",
-  "version": "0.0.1",
+  "version": "0.0.2",
   "description": "Type-safe Lens API for immutable updates in complex data structures",
@@ -5,0 +5,0 @@ "keywords": [

README.md

@@ -1,3 +0,1 @@
-# WIP - Implementing API
-
 # immutable-lens
@@ -7,3 +5,3 @@
 
-### Introduction
+### Features
  - No mutations
@@ -21,2 +19,13 @@ - Powerful API
 ```ts
+import {createLens} from 'immutable-lens'
+
+type State = {
+   user: {
+      name: string
+   }
+}
+const state: State = {user: {name: 'Bob'}}
+
+const lens = createLens<State>() // OR
+const lens = createLens(state)
 ```
@@ -26,6 +35,38 @@
 ```ts
+const userLens = lens.focusOn('user')
+const userNameLens = userLens.focusOn('name')
 ```
 
-#### Update
+#### Describe and apply updates
 ```ts
+const upperCaseUserName: (state: State) => State = 
+   // ALL EQUIVALENT
+   userNameLens.setValue('BOB')
+   userNameLens.update(name => name.toUpperCase())
+   userLens.setFieldValues({name: 'BOB'})
+   userLens.updateFields({name: (name) => name.toUpperCase()})
+   
+const updatedState = upperCaseUserName(state) 
+console.log(updatedState) // {user: {name: 'BOB'}}
 ```
+
+#### Optional types
+```ts
+type State = {
+   loggedUser?: {
+      name: string
+   }
+}
+const state: State = { ... }
+
+const lens = createLens<State>()
+const loggedUserLens = lens.focusOn('loggedUser')
+
+loggedUserLens.setValue(state, {name: 'Bob}) // OK
+loggedUserLens.update(state, loggedUser => ({name: 'Bob'})) // OK (Runtime error if loggedUser udefined)
+
+loggedUserLens.setFieldValues(state, { ... }) // ERROR: 
+loggedUserLens.defaultTo({ id: '', name: 'Default User' })
+```
+
+

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Major refactor

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Package has recently undergone a major refactor. It may be unstable or indicate significant internal changes. Use caution when updating to versions that include significant changes.

Found 1 instance in 1 package

Improved metrics

Total package byte prevSize

29442

increased by244.43%

Number of package files

30

increased by233.33%

Lines of code

393

increased by281.55%

Number of lines in readme file

70

increased by141.38%

Worsened metrics

Number of medium supply chain risk alerts

1

increased byInfinity%

No dependency changes