General Dev>In The News

A Perplexing Javascript Parsing Puzzle

CommunityNews

CommunityNews

A Perplexing Javascript Parsing Puzzle

What does this print?
x =1 x -->0 Think it through, then try it in a browser console! Answer and explanation in the dropdown.
Show answer

It prints 1.

wait wtf At the beginning of a line (and only at the beginning of a line), → starts a comment. The JavaScript is parsed as
x=1; x; // 0 The browser then displays the value of the last expression, which of course is 1.

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