Why can't variables be declared in a switch statement?

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一生所求
一生所求 2020-11-21 05:15

I\'ve always wondered this - why can\'t you declare variables after a case label in a switch statement? In C++ you can declare variables pretty much anywhere (and declaring

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  •  野性不改
    2020-11-21 06:02

    If your code says "int newVal=42" then you would reasonably expect that newVal is never uninitialised. But if you goto over this statement (which is what you're doing) then that's exactly what happens - newVal is in-scope but has not been assigned.

    If that is what you really meant to happen then the language requires to make it explicit by saying "int newVal; newVal = 42;". Otherwise you can limit the scope of newVal to the single case, which is more likely what you wanted.

    It may clarify things if you consider the same example but with "const int newVal = 42;"

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