#17: 1 < 2 < 3

Output

true

Why

JavaScript has no real concept of chained comparisons like math notation does — there's no special-casing for a < b < c meaning 'both a<b and b<c'. Instead, < is left-associative, so this parses as (1 < 2) < 3. The parenthesized part evaluates first to the boolean true, and then true < 3 coerces true to the number 1, giving 1 < 3, which is true. It works out here, but it's a coincidence of the specific numbers, not a real range check.

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