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JavaScript - Undefined Infinity or Not a Number?

Had a heated discussion with a friend about a particular expression and so this blog with ready references for some basic JavaScript expressions.

ExpressionValue
InfinityAnything beyond +/-1.7976931348623157e+308
typeof Infinity"number"
typeof NaN"number"
typeof undefined"undefined"
typeof null"object"
Infinity + InfinityInfinity
Infinity - InfinityNaN
-Infinity + InfinityNaN
Infinity / InfinityNaN
Infinity * InfinityInfinity
Infinity * 1Infinity
Infinity / 1Infinity
Infinity / 0Infinity
Infinity * 0NaN
Infinity - 1e308Infinity
Infinity - 1e309NaN
-Infinity + 1e308-Infinity
-Infinity + 1e309NaN
Infinity / 1e308Infinity
1 * "a"NaN
1 + NaNNaN
1 * NaNNaN
undefined + 1NaN
undefined * 1NaN
undefined + InfinityNaN
undefined * InfinityNaN
undefined + NaNNaN
undefined * NaNNaN
undefined + nullNaN
undefined * nullNaN
1 + null1
1 * null0
null + null0
null * null0
Infinity + nullInfinity
Infinity * nullNaN
NaN + nullNaN
NaN * nullNaN
"" + Infinity"Infinity"
"" + NaN"NaN"
"" + null"null"
"" + undefined"undefined"

Having fun yet ?

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