coerce

helper to coerce value to expected type
useful to parse query-string parameters

Install

npm install type-coerce

Usage

let coerce = require('type-coerce')
let val = coerce.int('123')
// val = 123

let arr = coerce.array('a,b,c')
// val = ['a', 'b', 'c']

API

• on success: => coerced value
• on failure: => undefined

coerce.int(val) => Number, an integer

coerce.floar(val) => Number

coerce.bool(val) => true or false

• true, 'true', 'True', 'TRUE', '1', 1 returns true
• false, 'false', 'False', 'FALSE', '0', 0 returns false
• anything else fails the coercion

coerce.string(val) => String

• if val is string => val
• otherwise, => util.inspect(val)

coerce.array(val, elemT, sep) => Array of String

• val:
  • string: parse into Array, split by sep, parse element by elemT
  • null, undefined: undefined
  • Array: parse elements with elemT
  • otherwise, [val]
• sep: explicitly specify separator, string or RegExp
  • default: \s*,\s*, this splits string with , and trims spaces
• elemT: element parser, (str)=>element
  • a function that parses array element
  • default: coerce.any
• sep or elemT can be omitted, or passed in reverse order

coerce.typedArray(sep, elemT) => (val)=>coerce.array(val, sep, elemT)

• create a partial initialized function to use later
• take sep, elemT as arguments

coerce.any(val) => val

• => val

coerce.date(val) => Date

• val is passed to new Date()

LICENSE

MIT (C) wacky6/Jiewei Qian