if-const - npm Package Compare versions

Comparing version 1.0.2 to 1.1.0

dist/es/index.js

@@ -1,6 +0,14 @@
-export function ifConst(cond, ...args) {
+const defaultComp = (val) => !!val;
+function _ifConst(cond, ...args) {
     var _a;
     return args[0]
-        ? (_a = (cond ? args[0] : args[1])) === null || _a === void 0 ? void 0 : _a(cond) : (f, elf) => ifConst(cond, f, elf);
+        ? (_a = (this.check(cond) ? args[0] : args[1])) === null || _a === void 0 ? void 0 : _a(cond) : _ifConst.bind(this, cond);
 }
+export const ifConst = _ifConst.bind({ check: defaultComp });
+ifConst.compare = (c) => {
+    return _ifConst.bind({ check: c });
+};
+ifConst.not = (value) => {
+    return _ifConst.bind({ check: (_) => _ !== value });
+};
 export default ifConst;
@@ -7,0 +15,0 @@ export function constIf(f, elf) {

dist/esnext/index.js

@@ -1,6 +0,14 @@
-export function ifConst(cond, ...args) {
+const defaultComp = (val) => !!val;
+function _ifConst(cond, ...args) {
     return args[0]
-        ? (cond ? args[0] : args[1])?.(cond)
-        : (f, elf) => ifConst(cond, f, elf);
+        ? (this.check(cond) ? args[0] : args[1])?.(cond)
+        : _ifConst.bind(this, cond);
 }
+export const ifConst = _ifConst.bind({ check: defaultComp });
+ifConst.compare = (c) => {
+    return _ifConst.bind({ check: c });
+};
+ifConst.not = (value) => {
+    return _ifConst.bind({ check: (_) => _ !== value });
+};
 export default ifConst;
@@ -7,0 +15,0 @@ export function constIf(f, elf) {

dist/js/index.js

 "use strict";
 Object.defineProperty(exports, "__esModule", { value: true });
 exports.constIf = exports.ifConst = void 0;
-function ifConst(cond, ...args) {
+const defaultComp = (val) => !!val;
+function _ifConst(cond, ...args) {
     var _a;
     return args[0]
-        ? (_a = (cond ? args[0] : args[1])) === null || _a === void 0 ? void 0 : _a(cond) : (f, elf) => ifConst(cond, f, elf);
+        ? (_a = (this.check(cond) ? args[0] : args[1])) === null || _a === void 0 ? void 0 : _a(cond) : _ifConst.bind(this, cond);
 }
-exports.ifConst = ifConst;
-exports.default = ifConst;
+exports.ifConst = _ifConst.bind({ check: defaultComp });
+exports.ifConst.compare = (c) => {
+    return _ifConst.bind({ check: c });
+};
+exports.ifConst.not = (value) => {
+    return _ifConst.bind({ check: (_) => _ !== value });
+};
+exports.default = exports.ifConst;
 function constIf(f, elf) {
-    return cond => ifConst(cond, f, elf);
+    return cond => exports.ifConst(cond, f, elf);
 }
 exports.constIf = constIf;
 //# sourceMappingURL=index.js.map

dist/umd.js

@@ -1,2 +0,2 @@
-!function(e,n){"object"==typeof exports&&"undefined"!=typeof module?n(exports):"function"==typeof define&&define.amd?define(["exports"],n):n((e="undefined"!=typeof globalThis?globalThis:e||self)["if-const"]={})}(this,(function(e){"use strict";function n(e){var t;return(arguments.length<=1?void 0:arguments[1])?null===(t=e?arguments.length<=1?void 0:arguments[1]:arguments.length<=2?void 0:arguments[2])||void 0===t?void 0:t(e):function(t,o){return n(e,t,o)}}e.constIf=function(e,t){return function(o){return n(o,e,t)}},e.default=n,e.ifConst=n,Object.defineProperty(e,"__esModule",{value:!0})}));
+!function(n,e){"object"==typeof exports&&"undefined"!=typeof module?e(exports):"function"==typeof define&&define.amd?define(["exports"],e):e((n="undefined"!=typeof globalThis?globalThis:n||self)["if-const"]={})}(this,(function(n){"use strict";function e(n){var t;return(arguments.length<=1?void 0:arguments[1])?null===(t=this.check(n)?arguments.length<=1?void 0:arguments[1]:arguments.length<=2?void 0:arguments[2])||void 0===t?void 0:t(n):e.bind(this,n)}var t=e.bind({check:function(n){return!!n}});t.compare=function(n){return e.bind({check:n})},t.not=function(n){return e.bind({check:function(e){return e!==n}})},n.constIf=function(n,e){return function(i){return t(i,n,e)}},n.default=t,n.ifConst=t,Object.defineProperty(n,"__esModule",{value:!0})}));
 //# sourceMappingURL=umd.js.map

package.json

 {
   "name": "if-const",
-  "version": "1.0.2",
+  "version": "1.1.0",
   "sideEffects": false,
@@ -5,0 +5,0 @@ "description": "Executes blocks of code depending on thruthness of the value, while also making the value accessible to the block",

README.md

@@ -17,3 +17,35 @@ # if-const [![NPM version](https://img.shields.io/npm/v/if-const.svg?style=flat-square)](https://www.npmjs.com/package/if-const) [![NPM monthly downloads](https://img.shields.io/npm/dm/if-const.svg?style=flat-square)](https://npmjs.org/package/if-const) [![NPM total downloads](https://img.shields.io/npm/dt/if-const.svg?style=flat-square)](https://npmjs.org/package/if-const) [![Linux Build Status](https://img.shields.io/travis/raiondesu/if-const.svg?style=flat-square)](https://travis-ci.com/raiondesu/if-const) [![Linux Build Status](https://img.shields.io/coveralls/github/Raiondesu/if-const?style=flat-square)](https://travis-ci.com/raiondesu/if-const)
 
-Works with any type of conditional that a normal `if` works with.\
+Imangine you have a faulty third-party function that can return a falsy value in some cases.\
+It's often needed to just get the "truthy" value from that function, quickly do something with it, and forget about it:
+
+```ts
+// returns either null or an object of some sort
+import { nullOrObj } from './some-module';
+
+if (nullOrObj()) {
+  // how do we access the result?
+}
+
+// one might want to do this, but it's illegal in js
+if (const obj = nullOrObj()) {
+  obj
+}
+
+// And this is just tiring
+// What if we want to enforce its immutability?
+let obj;
+if (obj = nullOrObj()) {}
+```
+
+That's where `if-const` comes in:
+
+```ts
+ifConst(nullOrObj(), obj => {
+  // use the obj as you wish
+});
+```
+
+It's that simple!
+
+It works with any type of conditional that a normal `if` works with.\
 Allows to use the result of a conditional in a code block (similar to C# `out var` syntax).
@@ -93,2 +125,39 @@
 
+### Comparator
+
+If, for some reason, you need to check for some different condition (not falsyness), you can use the `.not` and `.compare` methods:
+
+```ts
+// For example, we need to check if the value is 0 or null
+const value = Math.random() > 0.5 ? null : 0;
+
+// Since 0 is falsy, we need a custom comparator for this
+
+// .not accepts a single value to `!==` against
+// Note that the logic here is negated!
+const ifNotNull = ifConst.not(null);
+
+// .compare accepts a complete comparator function
+const ifNotNull = ifConst.compare<null>(_ => _ !== null);
+
+ifNotNull(value, v => {
+  console.log('true', v, typeof v)
+}, n => {
+  console.log('false', n, typeof n)
+});
+// logs either
+// > true 0 number
+// or
+// > false null object
+
+
+// Or a shorter version:
+ifConst.not(null)(value, v => {
+  console.log('true', v, typeof v)
+}, n => {
+  console.log('false', n, typeof n)
+});
+```
+Which reads almost like plain english!
+
 ## About
@@ -95,0 +164,0 @@

src/index.ts

 export type Falsy = null | undefined | false | 0 | '';
 
-export type F<T, R> = (res: Exclude<T, Falsy>) => R;
-export type ELF<T, R> = (res: Extract<T, Falsy>) => R;
+export type F<T, R, U = Falsy> = (res: Exclude<T, U>) => R;
+export type ELF<T, R, U = Falsy> = (res: Extract<T, U>) => R;
 
@@ -10,15 +10,36 @@ type FP<T, R> = [f?: F<T, R>, elf?: ELF<T, R>];
 
-export function ifConst<T>(cond: T): {
-  <R>(f: F<T, R>): R | undefined
-  <R>(f: F<T, R>, elf: ELF<T, R>): R;
+type IfConst<U = Falsy> = {
+  <T>(value: T): {
+    <R>(f: F<T, R, U>): R | undefined
+    <R>(f: F<T, R, U>, elf: ELF<T, R, U>): R;
+  }
+  <T, R>(value: T, f: F<T, R, U>): R | undefined;
+  <T, R>(value: T, f: F<T, R, U>, elf: ELF<T, R, U>): R;
+  <T, R>(value: T, f?: F<T, R, U>, elf?: ELF<T, R, U>): R | undefined;
 }
-export function ifConst<T, R>(cond: T, f: F<T, R>): R | undefined;
-export function ifConst<T, R>(cond: T, f: F<T, R>, elf: ELF<T, R>): R;
-export function ifConst<T, R>(cond: T, f?: F<T, R>, elf?: ELF<T, R>): R | undefined;
-export function ifConst<T, R = never>(cond: T, ...args: FP<T, R>): R | undefined | FT<T, R> {
+
+type Comparator = (val: any) => boolean;
+
+type CompThis = { check: Comparator };
+
+const defaultComp: Comparator = (val: any) => !!val;
+
+function _ifConst<T, R>(this: CompThis, cond: T, ...args: FP<T, R>): FT<T, R> | R | undefined {
   return args[0]
-    ? (cond ? args[0] : args[1])?.(cond as any)
-    : (f, elf) => ifConst(cond, f, elf);
+    ? (this.check(cond) ? args[0] : args[1])?.(cond as any)
+    : _ifConst.bind(this, cond as unknown) as FT<T, R>;
 }
 
+export const ifConst: IfConst & {
+  compare<U>(comparator: Comparator): IfConst<U>;
+  not<U>(value: U): IfConst<U>;
+} = _ifConst.bind({ check: defaultComp }) as any;
+
+ifConst.compare = <U>(c: Comparator): IfConst<U> => {
+  return _ifConst.bind({ check: c }) as any;
+}
+ifConst.not = <U>(value: U): IfConst<U> => {
+  return _ifConst.bind({ check: (_: U) => _ !== value }) as any;
+}
+
 export default ifConst;
@@ -25,0 +46,0 @@

tsconfig.json

@@ -14,2 +14,4 @@ {
     "esModuleInterop": true,
+    "strictFunctionTypes": true,
+    "strictNullChecks": true,
     "skipLibCheck": true,
@@ -16,0 +18,0 @@ "skipDefaultLibCheck": true,

No alert changes

Improved metrics

Total package byte prevSize

23456

increased by28.66%

Lines of code

139

increased by40.4%

Number of lines in readme file

180

increased by62.16%

No dependency changes