Add array/removeAt (#47)

* Add removeAt method

Co-authored-by: krystianborucinski <krystian.borucinski@sandstream.pl>

Author: 2 people

README.md

@@ -387,6 +387,30 @@ Generates an array of numbers from 0 to n - 1.
 ```
 <!-- prettier-ignore-end -->
 
+#### removeAt
+
+Removes an element at the given index from the given array.
+
+##### Type signature
+
+<!-- prettier-ignore-start -->
+```typescript
+(index: number) => (xs: any[]) => any[]
+```
+<!-- prettier-ignore-end -->
+
+##### Examples
+
+<!-- prettier-ignore-start -->
+```javascript
+removeAt(3)([1, 2, 3, 4, 5, 6]) // ⇒ [1, 2, 3, 5, 6]
+```
+<!-- prettier-ignore-end -->
+
+##### Questions
+
+- How to remove an item at a particular index?
+
 #### repeat
 
 Repeats the given element by given count of times.

array/README.md

@@ -370,6 +370,30 @@ Generates an array of numbers from 0 to n - 1.
 ```
 <!-- prettier-ignore-end -->
 
+# removeAt
+
+Removes an element at the given index from the given array.
+
+## Type signature
+
+<!-- prettier-ignore-start -->
+```typescript
+(index: number) => (xs: any[]) => any[]
+```
+<!-- prettier-ignore-end -->
+
+## Examples
+
+<!-- prettier-ignore-start -->
+```javascript
+removeAt(3)([1, 2, 3, 4, 5, 6]) // ⇒ [1, 2, 3, 5, 6]
+```
+<!-- prettier-ignore-end -->
+
+## Questions
+
+- How to remove an item at a particular index?
+
 # repeat
 
 Repeats the given element by given count of times.

array/index.js

@@ -24,6 +24,7 @@ import multiple from "./multiple.js";
 import none from "./none.js";
 import partition from "./partition.js";
 import range from "./range.js";
+import removeAt from "./removeAt.js";
 import repeat from "./repeat.js";
 import reverse from "./reverse.js";
 import reverseIf from "./reverseIf.js";
@@ -71,6 +72,7 @@ export {
   none,
   partition,
   range,
+  removeAt,
   repeat,
   reverse,
   reverseIf,
@@ -119,6 +121,7 @@ export default {
   none,
   partition,
   range,
+  removeAt,
   repeat,
   reverse,
   reverseIf,

array/index.ts

@@ -24,6 +24,7 @@ import multiple from "./multiple";
 import none from "./none";
 import partition from "./partition";
 import range from "./range";
+import removeAt from "./removeAt";
 import repeat from "./repeat";
 import reverse from "./reverse";
 import reverseIf from "./reverseIf";
@@ -71,6 +72,7 @@ export {
   none,
   partition,
   range,
+  removeAt,
   repeat,
   reverse,
   reverseIf,
@@ -119,6 +121,7 @@ export default {
   none,
   partition,
   range,
+  removeAt,
   repeat,
   reverse,
   reverseIf,

array/removeAt.js

@@ -0,0 +1,10 @@
+export default index => xs => {
+  if (index >= xs.length || index < 0) {
+    return xs;
+  }
+
+  const ys = [...xs];
+  ys.splice(index, 1);
+
+  return ys;
+};

array/removeAt.json

@@ -0,0 +1,12 @@
+{
+  "name": "removeAt",
+  "description": "Removes an element at the given index from the given array.",
+  "signature": "(index: number) => (xs: any[]) => any[]",
+  "examples": [
+    {
+      "language": "javascript",
+      "content": "removeAt(3)([1, 2, 3, 4, 5, 6]) // ⇒ [1, 2, 3, 5, 6]"
+    }
+  ],
+  "questions": ["How to remove an item at a particular index?"]
+}

array/removeAt.md

@@ -0,0 +1,23 @@
+# removeAt
+
+Removes an element at the given index from the given array.
+
+## Type signature
+
+<!-- prettier-ignore-start -->
+```typescript
+(index: number) => (xs: any[]) => any[]
+```
+<!-- prettier-ignore-end -->
+
+## Examples
+
+<!-- prettier-ignore-start -->
+```javascript
+removeAt(3)([1, 2, 3, 4, 5, 6]) // ⇒ [1, 2, 3, 5, 6]
+```
+<!-- prettier-ignore-end -->
+
+## Questions
+
+- How to remove an item at a particular index?

array/removeAt.test.ts

@@ -0,0 +1,16 @@
+/* eslint-env jest */
+// @ts-ignore ambiguous import
+import removeAt from "./removeAt.ts";
+
+describe("removeAt", () => {
+  it("should remove an element at the specified index", () => {
+    expect(removeAt(3)([1, 2, 3, 4, 5, 6])).toEqual([1, 2, 3, 5, 6]);
+  });
+
+  it("should do nothing when given an index out of range", () => {
+    expect(removeAt(3)([])).toEqual([]);
+    expect(removeAt(-1)([])).toEqual([]);
+    expect(removeAt(3)([1, 2, 3])).toEqual([1, 2, 3]);
+    expect(removeAt(-1)([1, 2, 3])).toEqual([1, 2, 3]);
+  });
+});

array/removeAt.ts

@@ -0,0 +1,10 @@
+export default (index: number) => (xs: any[]) => {
+  if (index >= xs.length || index < 0) {
+    return xs;
+  }
+
+  const ys = [...xs];
+  ys.splice(index, 1);
+
+  return ys;
+};