I have a large form with many fields and a special processing function
Several variables of different types declared at the beginning of a function

I would like to check that a user has set all variables before a function execution

const a1 = true, a2 = "str", a3 = { b: true }, a4 = [], a5 = "";

// Variant 1: old school
if (!(a1 && a2 && a3 && a4 && a5))
  return toast.error('Please fill out all fields');

// Variant 2: array aggregation
if (!Array.of(a1, a2, a3, a4, a5).every(Boolean))
  return toast.error('Please fill out all fields');

I would like to catch a5, since it's an empty string

Variant 1 is not readable if we have 5 variables and not very elegant
Variant 2 is more elegant and clear but doesn't work for variables of not type Boolean

How do you check lots of variables in one pass?

CodePudding user response：

Would that work for you?

const hasTruthyInput = v => typeof v === 'string' ? v.trim().length > 0 : Boolean(v);

// Variant 2: array aggregation
if (!Array.of(a1, a2, a3, a4, a5).every(hasTruthyInput))
  return toast.error('Please fill out all fields');

I used v.trim() to make it harder for the user to circumvent the form by entering a string full of whitespaces. Adjust to your needs.