'no user-defined conversion exists' error

[Anna]

I have two data types in my program:

Foo1 and
FooTD (which is a typedef of type Foo2)

Foo1 has an operator= function which takes a const& to Foo2 as input
and assigns it to a Foo1 type.

The statement

Foo1 f = getFooTD();

where getFooTD() returns a Foo2 doesn't compile. I get the 'no
user-defined conversion exists' error.

However, the following works:

Foo1 f;
f = getFooTD();

There's probably something very obvious that I'm missing here. Anyone
knows why I get the error?

Thanks.

 

[red floyd]

I have two data types in my program:

Foo1 and
FooTD (which is a typedef of type Foo2)

Foo1 has an operator= function which takes a const& to Foo2 as input
and assigns it to a Foo1 type.

The statement

Foo1 f = getFooTD();

where getFooTD() returns a Foo2 doesn't compile. I get the 'no
user-defined conversion exists' error.

However, the following works:

Foo1 f;
f = getFooTD();

There's probably something very obvious that I'm missing here. Anyone
knows why I get the error?

Yes. Foo1 f = getFooTD() is construction, not assignment. It's
semantically equivalent to:

Foo1 f(getFooTD()).

You need a constructor for Foo1 that takes a Foo2.