Check if all array elements are equal to a given value

Compare every item with a value using ===.

JavaScript Version 1.0.0 · MIT · .md

function isEqual({ values, value }) { return values.every(item => item === value); }

Input & expected output

{
  "values": [
    "delivered",
    "delivered"
  ],
  "value": "delivered"
}

true

The edge case

{
  "values": [],
  "value": "delivered"
}

true

Know the limits

• An empty array returns true: no item differs.
• Strict equality: "1" and 1 are different.

The function above is the implementation used by the lab. The lab validates JSON types and caps size before execution; include equivalent validation when accepting untrusted input in your application.

Keep exploring

• Check whether all values are equal — Compare every item with the first using Object.is.
• Check whether an object is empty — Check for own enumerable string keys on a JSON object.
• Check whether an integer is even — Test parity for safe integers, including zero and negative values.