javascript - How come "minus, space, minus" evaluates to the "plus" operator? -

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node -e 'console.log(- -1)' // prints 1 makes sense

however:

node -e 'console.log(1 - - 1)' // prints 2 not make sense me

integer - - integer magically converts "minus, space, minus" "plus" operator. why?

update: seems wasn't clear enough. question not why double negative in mathematics evaluate positive how magically evaluates + operator; these 2 different scenarios - making negative number positive 1 thing, invoking implicitly + thing.

makes perfect sense, double negative in mathematics evaluate positive


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