JavaScript NaN equvialence -

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• what rationale comparisons returning false ieee754 nan values? 12 answers

just fun trying compare value set nan value set nan.

why 2 variables, identical values, not equivalent?

var = number.nan var b = number.nan === b false  == b false  var = nan var b = nan === b  false == b false 

why happen?

nan not number, there no evaluated numberic value compare - use isnan() compare nan values. w3 schools link