javascript - Why does [] + [] return an empty string? -

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lately have been experimenting node.js , found out javascript has syntactic logic not wrap head around. example not understand , wondering whether random javascript fact or if there logic it.

the plus sign either arithmetic plus or string concatenation. empty arrays converted empty strings in case of [] + [].

the array's tostring method return 1 string comma separated list of of array's elements.

from the mdn reference above:

javascript calls tostring method automatically when array represented text value or when array referred in string concatenation.

the same idea of automatic type conversion why true + true === 2, , type conversion basis of many tricky javascript quizzes this one.


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