🚀 go-pugleaf

Hello,

I read section 6.4 carefully but I couldn't decide what the lifetime (not
scope) of an object declared in the condition of a while or for statements
is.  Reading D&E 3.11.5.2 didn't help either.  Given the following:

struct T { T(int); ~T(); operator bool() const; /*...*/ };

void f(int i)
    {
    while (T t = i) { /* do something with 't' */ }
    }

There are two "obvious" possibilities, I9m leaning toward the first:

1 -- The object is initialized just once and destroyed just once, making
'f' above eqivalent to:

void f(int i)
    {
        {
        T t = i;
        while (t) { /* do something with 't' */ }
        }
    }

2 -- the object is initialized and destroyed on each iteration, making 'f'
above eqivalent to:

void f(int i)
    {
    while (1) { T t = i; if (!t) break; /* do something with 't' */ }
    }

Which is it supposed to be?

Bonus question:  why does the grammer allow only the '=
assignment-expression' form:

          condition:
                  expression
                  type-specifier-seq declarator = assignment-expression
 
instead of:

          condition:
                  expression
                  type-specifier-seq declarator = assignment-expression
                  type-specifier-seq declarator ( expression-list )
 
So that I could write:

void f(int i)
    {
    while (T t(i)) { /* do something with 't' */ }
    }

Which I prefer.

[I was tempted to suggest the tidier

          condition:
                  expression
                  type-specifier-seq declarator initializer

but that would allow the potentially disagreeable '= { /*...*/ }' form.]

Thanks for your kind attention,
    --scott
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