isNull()

isNull(value): value is null

Checks if a value is null.

note

Only checks null, not undefined. Use isNil to check both.

---

Parameters

value: unknown

The value to check.

---

Returns: value is null

true if the value is null, false otherwise.

---

See Also

• isNil
• isUndefined
• isNonNull

---

Since

1.0.0

---

Example

isNull(null);      // => true
isNull(undefined); // => false
isNull(0);         // => false
isNull('');        // => false

---

How it works?

Type guard that checks if a value is null.

Type Narrowing

Common Checks

Value	Result
null	true
undefined	false
0	false
''	false
false	false

vs isNil

---

Use Cases

Detect explicit absence 📌

Check strictly for null values. Essential for differentiating between "no value" (null) and "not set" (undefined).

#detect#null#absence#explicit#validation#semantic

if (isNull(record.deletedAt)) {
  // Record is active (deletedAt is explicitly null)
}