Combinations

Sometimes we allow function to accept different sequences of types. Let’s take an example:

function andLogAndFinish( spec, tracker, done ) {
  validate( "SOF|SZF|OOF|OZF", [ spec, tracker, done ] )
  //...
}

Where the following sequences of types valid:

• string, object, function

• string, null, function

• object, object, function

• object, null, function

import { validateCombo } from "bycontract";

const CASE1 = [ "string", TRACKER_OPTIONS, "function" ],
      CASE2 = [ "string", null, "function" ],
      CASE3 = [ SPEC_OPTIONS, TRACKER_OPTIONS, "function" ],
      CASE4 = [ SPEC_OPTIONS, null, "function" ];

validateCombo( arguments, [ CASE1, CASE2, CASE3, CASE4 ] );

Function validateCombo throws exception when none of the cases is valid