Berkeley CSUA MOTD:Entry 32574
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2025/05/24 [General] UID:1000 Activity:popular
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2004/7/29-30 [Computer/SW/Languages/C_Cplusplus] UID:32574 Activity:moderate
7/29    How do I describe scope in C?  Is it outer/inner scope?  Higher/lower
        scope?  Parent/child scope?  I forgot.  Thanks.
        \_ "Trivial C Question Troll", I love you!
        \_ you're thinking in OO terms. C has "local" and "global" scope.
           \_ C99 has more than two levels of scope.  For instance, each for
              loop has its own scope.  Also, gcc lets you define functions
              inside other functions, as a (non-standard) extension. -- ilyas
              \_ Hasn't it always been the case that each pair of {} has its
                 own scope, even before C99?
                 \_ Yeah you are right. -- ilyas
                 \_ Yes.
           \_ I was going to say that, but was afraid the OP might be more leet
              than me.
           \_ What I'm thinking is something like:
                void foo(void) {
                  ... code 1 ...
                  {
                    int i;
                    ... code 2 ...
                    {
                      ... code 3 ...
                    }
                  }
                }
              So "i" is defined in code 2 and 3, but not in code 1.  How do I
              describe this?
              \_ The scope in C is really simple, it's based on block scoping
                 where the blocks are defined by curly braces.
                 If it's at the beginning of a curly, it's scope is anything
                 between the curlys, ergo the term "block." Some people call
                 it "area scoping" defined by the "area" of code defined by
                 the braces. Some others call it "brace" scoping.
              \_ If code 3 is not a function called from code 2, you just
                 answered your own question.
                 \_ You can't define a function inside another function in C.
                    \_ Duh.  But code 3 could be a function call that needs 'i'
                    \_ Huh?  I thought the op is talking about nested inner
                       blocks.  Who said anything about functions?
              \_ i is in scope in code 2 and 3, but not in scope in code 1.
        \_ Although this isn't the example you are giving are you thinking
           about lexical vs dynamic scope?
           \_ The original question is just that which pair of adjectives to
              use to describe the scopes in the same file.
              \_ Nested.  Inner.  Take your pick.
2025/05/24 [General] UID:1000 Activity:popular
5/24    

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