c++ - What is the difference between 'typedef' and 'using' in C++11?

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I know that in C++11 we can
now use using to write type alias, like
typedefs:

typedef
            int MyInt;

Is, from
what I understand, equivalent
to:

using MyInt =
            int;

And
that new syntax emerged from the effort to have a way to express "template
typedef":

template<
            class T > using MyType = AnotherType< T, MyAllocatorType
            >;

But, with the
first two non-template examples, are there any other subtle differences in the standard?
For example, typedefs do aliasing in a "weak" way. That is it
does not create a new type but only a new name (conversions are implicit between those
names).

Is it the same with
using or does it generate a new type? Are there any
differences?

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class="normal">Answer

They are equivalent, from the
standard (emphasis mine)
(7.1.3.2):

A
typedef-name can also be introduced by an alias-declaration. The
identifier
following the using keyword becomes a typedef-name and the
optional
attribute-specifier-seq following the identifier appertains
to that
typedef-name. It has the same semantics as if it were

introduced by the typedef specifier. In particular, it
does
not define a new type and it shall not appear in the
type-id.