numbers - JavaScript type conversion: (true && 1) vs (true | | 1)

Question

JavaScript is non-strictly typed language as Java,for example.

As we know, it converts value of result dependently upon context:

"2" + "3" results "23"

"2" * "3" results 6

This is quite clear and OK for understanding.

I just tried following expressions and got confused:

true && 1 results 1
true || 1 results true

Why the first gives Number and the second gives boolean?

Considering JavaScript conversion rules,I expect to get boolean values in both cases,due to boolean context of expression.

Answer 1

To quote MDC;

&&; Returns expr1 if it can be converted to false; otherwise, returns expr2. Thus, when used with Boolean values, && returns true if both operands are true; otherwise, returns false.

||; Returns expr1 if it can be converted to true; otherwise, returns expr2. Thus, when used with Boolean values, || returns true if either operand is true; if both are false, returns false.

So in the first example, 1 is being returned because expr1 cannot be converted to false.

In the second example, true can be converted to true, so it's returned.