🚀 go-pugleaf

rmartin@rcmcon.com (Robert Martin) wrote:
>
>In reading the WP I see that the scope of variables declared in 'for'
>statements is now identical with the scope of variables declared in
>'if' and 'while' statements.  i.e. any variable declared in a 'for',
>'if' or 'while' statement is local to the statement, and to the
>controlled statement, but not to the enclosing scope.


   In fact, the WP is not clear, and is probably inconsistent
about all these cases. It isn't clear which scope
such a declared variable is in. Consider:

   if(int i=0)int i;      //#1 ambiguous wording in the WP
   if(int i=0){ int i; }  //#2 ambiguous wording in the WP
   if(int i=0){{int i; }} // definitely legal


The WP mumbles incomprehensibly about not being allowed to
redeclare the control variable in the outer scope of the
controlled statement. This is not supported by the grammar:

  if-statement:
    "if" "(" cond ")" statement

in which statement can be a compound statement. By this grammar
#2 cannot be sensibly disallowed. Instead one would need
an extra production:

     "if" "(" cond ")" "{" statement-list "}"

in which the {} extend the scope of the condition rather
than introducing a new scope NESTED in the scope of the
condition.






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John Max Skaller               voice: 61-2-566-2189
81 Glebe Point Rd              fax:   61-2-660-0850
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