What is a unary function?
Interviewer Expectations for this Question
01
Core Competency
Assesses fundamental understanding of JavaScript conventions, runtime behavior, and memory/performance considerations.
02
Evaluation Criteria
Hiring managers look for precision, avoidance of ambiguous jargon, and ability to explain trade-offs under real production conditions.
Comprehensive Model Answer
Verified Solution
A unary function (also known as a monadic function) is a function that accepts exactly one argument. The term "unary" simply refers to the function's arity—the number of arguments it takes.
Let us take an example of unary function,
const unaryFunction = (a) => console.log(a + 10); // This will add 10 to the input and log the result
unaryFunction(5); // Output: 15
In this example:
unaryFunctiontakes a single parametera, making it a unary function.- It performs a simple operation: adding 10 to the input and printing the result.
Candidate Response Strategy & Interview Tips
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