str2num

This module is written on typescript, and contains the .d.ts file. If you write on typescript: just use it in your project and definitions will be automatically uploaded.

npm i -S str2num

About

Strict way to convert a string to a number. If the string does not contain the number then will be thrown the error.

Exports

export default function str2num(value: string|number): number;
export function isNum(value: any): boolean;

Examples

const str2num = require('str2num')
const assert = require('assert')

assert.equal(str2num(1000), 1000)
assert.equal(str2num('1000'), 1000)
assert.equal(str2num(' + 1,000 '), 1000)
assert.equal(str2num('- 1 000'), -1000)

assert.equal(str2num('-0'), -0)
assert.equal(str2num('1.20'), 1.2)
assert.equal(str2num('.120'), 0.12)
assert.equal(str2num('120.'), 120)

assert.equal(str2num('-.123e3'), -123)
assert.equal(str2num('-.123e+3'), -123)
assert.equal(str2num('-123e-3'), -0.123)

assert.equal(str2num('-Infinity'), -Infinity)
assert.equal(isNaN(str2num('NaN')), isNaN(NaN))

assert.equal(str2num(new Number(-1)), -1)
assert.equal(str2num(new String('-1')), -1)

assert.throws(() => str2num([]))
assert.throws(() => str2num({}))
assert.throws(() => str2num(/./))

assert.throws(() => str2num(''))
assert.throws(() => str2num('.'))
assert.throws(() => str2num('e'))
assert.throws(() => str2num('.e'))
assert.throws(() => str2num('.e3'))
assert.throws(() => str2num('-123e'))
assert.throws(() => str2num('e123'))

const isNum = require('str2num').isNum
const assert = require('assert')

assert.ok(isNum(Infinity))
assert.ok(isNum('Infinity'))
assert.ok(isNum('- 123, 456 .1e1'))

assert.ok(isNum(new Number(-1)))
assert.ok(isNum(new String('-1')))

assert.ok(!isNum([]))
assert.ok(!isNum({}))
assert.ok(!isNum(/.*/))