javascript - What happens when a number has a leading zero? -

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i've been trying debug problem today , found out problem is. reason, when number has leading 0 javascript weird.

example:

alert(132); alert(0132);  var test = 0132; alert(test);

jsfiddle: http://jsfiddle.net/u8sfu/3/

the first popup says "132," second "90," , third says "90."

my question is, why number 0132 become number 90? baffling me!

a number leading 0 parsed octal literal, in base 8.


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