linux - Why are both "true" and "false" tests true? -


the words "true" , "false" special words (builtins) bash. if used in if test, act intuitively expected:

$ if true; echo "true"; else echo "false"; fi true $ if false; echo "true"; else echo "false"; fi false

however, 2 tests:

$ [[ true ]] && echo "true" || echo "false" true $ [[ false ]] && echo "true" || echo "false" true

both result in true. why?

[[ … ]] is, in case, equivalent test, i.e. test true , test false. looking @ manual test(1):

-n string length of string nonzero

string equivalent -n string

true , false both non-empty strings.


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