Type Integrity Guard

Professional Type Guards

A common error in logic is checking for a string's length without verifying if it is actually a string. If the value is null, checking .length will crash your script.

A "Strong Type Guard" checks both the type and the value property in a single safe expression.

The Assignment

Your function receives a parameter val.

1. Check if val is strictly a string.
2. check if the string has at least one character (length > 0).
3. Return true only if both are true. Return false for empty strings, numbers, or null/undefined.