feat: add rang and isNullOrEmpty utils

src/array.ts

@@ -4,3 +4,12 @@
  * @returns array of given value
  */
 export const forceArray = (x: any) => (Array.isArray(x) ? x : [x]);
+
+/**
+ * create array of length n with from offset
+ * @param {number} len
+ * @param {number} [offset=0]
+ * @param {number} [step=1]
+ */
+export const range = (len: number, offset: number = 0, step: number = 1) =>
+  [...Array(len).keys()].map(i => i * step + offset);

src/number.ts

@@ -14,15 +14,15 @@ export const isNumber = (n: any) => typeof n === 'number' && !Number.isNaN(n);
  * @returns result | fallback
  */
 export const safeDivide = (dividend: number, divisor: number, fallback: any = 0) =>
-  divisor === 0 ? 0 : dividend / divisor;
+  divisor === 0 ? fallback : dividend / divisor;
 
 /**
  * clamp a number between two values
  * @param {number} value
  * @param {number[]} [[min, max]=[0, 1]]
  * @returns clamped number
  */
-export const clamp = (value: number, [min, max] = [0, 1]) => Math.max(Math.min(value, max), min);
+export const clamp = (value: number, [min, max]: number[] = [0, 1]) => Math.max(Math.min(value, max), min);
 
 /**
  * returns percentage value of a number from a maximum number

src/string.ts

@@ -31,7 +31,7 @@ export const kebabToCamel = (str: string) =>
  * @example
  * getInitials('frontend monsters'); // FM
  */
-export const getInitials = (name: string, fallback = '?') =>
+export const getInitials = (name: string, fallback: string = '?') =>
   typeof name === 'string' && name.length > 0
     ? name
         .replace(/\s+/g, ' ')
@@ -40,3 +40,10 @@ export const getInitials = (name: string, fallback = '?') =>
         .map(v => v && v[0].toUpperCase())
         .join('')
     : fallback;
+
+/**
+ * check if string is null or empty string
+ * @param {string} str
+ * @returns
+ */
+export const isNullOrEmpty = (str: string) => str == null || str === '';

tsconfig.json

@@ -7,6 +7,7 @@
       "dom",
       "es2018"
     ],
+    "downlevelIteration": true,
     "sourceMap": true,
     "declaration": true,
     "declarationDir": "lib/types",