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Will JavaScript detect the keying error in the following example?

publish date: 2022/09/06 01:54:00 GMT+10

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suppose that in a particular JavaScript program, i and x are currently the names of scalar numeric variables and y is currently the name of an array. Furthermore, suppose that the program needs the assignment statement

i = x;

but because of a keying error, it has the assignment statement

i = y;

Correct Answer

No

Explanation

In JavaScript (or any other language that uses dynamic type binding), no error is detected in this statement by the interpreter—the type of the variable named i is simply changed to an array. But later uses of i will expect it to be a scalar, and correct results will be impossible. In a language with static type binding, such as Java, the compiler would detect the error in the assignment i = y, and the program would not get to execution.

Reference

Concepts of Programming languages, 10th ed

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