for and visual c++ 6.0
Author
today i started programming under windows with visual c++ 6.0
Before, i''ve only used borland or g++ under linux, and i''ve found something strange.
if i do :
for(int i=0;i<10;i++)
{
...
}
i can still access i after the } and i cannot declare int i after that for..
that''s annoying because if i have to make another for just after, i have to use
for(i=0:i<10;i++)
{...}
That code can''t be compiled with g++ under linux, and if i use int i in the 2nd for, visual c++ won''t compile with the following error.
error C2374: ''i'' : redefinition; multiple initialization
any ideas why visual c++ act so strangely?
i haven''t touched the compilations options, they are the ones by default when creating an empty project.
It doesn''t conform to the C++ standard in this aspect. Visual Studio .NET fixed this (I think, though I''m pretty sure).
I dont understand what the problem with that is, why not just say.
int i;
for(i=0;i<10;i++)
{
...
}
for(i=0;i<10;i++)
{
...
}
or
for(int i=0;i<10;i++)
{
...
}
for(int j=0;j<10;j++)
{
...
}
???
int i;
for(i=0;i<10;i++)
{
...
}
for(i=0;i<10;i++)
{
...
}
or
for(int i=0;i<10;i++)
{
...
}
for(int j=0;j<10;j++)
{
...
}
???
I think it was
for(int i = 0; i < 10; i++)
{...}
for(i = 11; i < 20; i++) // notice i left out "int"
{...}
for(int i = 0; i < 10; i++)
{...}
for(i = 11; i < 20; i++) // notice i left out "int"
{...}
Author
my problem is that the scope for a variable is between { and }
maybe i''m wrong but i''ve always been told that
if i do
for(int i=0;i<10;i++)
{
...
}
//there the variable i doesn''t exist, so i can make another one.
// for ex
int i = 5;
with g++ it''s ok it follows that rule
but with visual c++
the variable i still exists after the }
and i don''t want that to happen because the code won''t be portable under linux.
after the 1st for
i can''t make int i=5, because it says that the variable i already exists. Maybe it''s a feature of visual c++, but i would like the compiler to act as the norm says, and i don''t know how...
maybe i''m wrong but i''ve always been told that
if i do
for(int i=0;i<10;i++)
{
...
}
//there the variable i doesn''t exist, so i can make another one.
// for ex
int i = 5;
with g++ it''s ok it follows that rule
but with visual c++
the variable i still exists after the }
and i don''t want that to happen because the code won''t be portable under linux.
after the 1st for
i can''t make int i=5, because it says that the variable i already exists. Maybe it''s a feature of visual c++, but i would like the compiler to act as the norm says, and i don''t know how...
quote:Original post by Anonymous Poster
I dont understand what the problem with that is, why not just say.
or
for(int i=0;i<10;i++)
{
...
}
for(int j=0;j<10;j++)
{
...
}
???
I think this jumps as double declaration in VC++
Author
yes it''s double declaration ant that''s the pb...
maybe i''ll have to swith to visual studio .net if that''s fixed.
maybe for you it''s not a bug, but for me it''s a huge one
maybe i''ll have to swith to visual studio .net if that''s fixed.
maybe for you it''s not a bug, but for me it''s a huge one
quote:Original post by owlquote:Original post by Anonymous Poster
I dont understand what the problem with that is, why not just say.
or
for(int i=0;i<10;i++)
{
...
}
for(int j=0;j<10;j++)
{
...
}
???
I think this jumps as double declaration in VC++
I dont think that is a double decleration, i changed the variable name to ''j'' the second time.
quote:Original post by Anonymous Posterquote:Original post by owlquote:Original post by Anonymous Poster
I dont understand what the problem with that is, why not just say.
or
for(int i=0;i<10;i++)
{
...
}
for(int j=0;j<10;j++)
{
...
}
???
I think this jumps as double declaration in VC++
I dont think that is a double decleration, i changed the variable name to ''j'' the second time.
Oh, look at that!
This was one of those controversial "breaking changes" between pre-ansi and ansi C++ that microsoft chose to support the old behavior for VC6. I remember seeing an article somewhere on microsoft.com sugesting that you do the following trick/hack/kludge to get the right behavior on VC6:
#define for if ( true ) for
#define for if ( true ) for
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