imkrimerman/im.val

Default value assigner for ES5 with checker

im.val

Default value assigner for ES5. If you hate to check for provided parameters in functions and methods then check this out.

Installation

npm install im.val --save

Usage

Returns value if value is provided, not undefined and not null, otherwise returns defaults.

If defaults is not provided, notDefined ($__NULL__$) value will be returned.

Additionally you can pass function as the 3rd parameter, it should validate value and return boolean. If function returns true then value will be returned, otherwise defaults.

var val = require('im.val'),
  _ = require('lodash');

// Using default value if options param is not provided
function getOptions (options) {
  return val(options, {});
}
console.log(getOptions());
// Logs {}

// Additional validation
function getOptionsCheck (options) {
  return val(options, {}, _.isObject);
}
console.log(getOptionsCheck('config'));
// Logs {}

function check (param) {
  var msg = 'Defined';
  if (val(param) === val.notDefined) msg = 'Not defined';
  console.log(msg);
}
check();
// Logs Not defined
check(undefined);
// Logs Not defined
check('Param');
// Logs Defined