Re: [Discuss-gnuradio] a two blocks synchronizing problem

[Marcus Müller]

Sorry, typo:

...
>  then your arguments must have types but need to be identifiers and can be 
> expressions that give you a value
...
is wrong,
needs to read
>  can *not* be expressions that give you a value
Full text, corrected:

>> In another topic, you wrote me that was syntactically incorrect and you
>> advice me to set it like this:
>> set_output_multiple(tamano_entrada+nsimbolo);
>>
>> But this way I get the errors <‘tamano_entrada’ is not a type> and <expected
>> ‘,’ or ‘...’ before ‘+’ token> 
> Different things are correct to do different things: When you call a
> function, you must not say which types the parameters have.
> If you do something that your compiler thinks is a function declaration,
> you must.
>
>> Again, when I set this parameters the first time I asked (void
>> set_output_multiple (int tamano_entrada + nsimbolo);
>>      void set_relative_rate (double relative_rate);) I did not get any 
>> errors,
> I'd like to address these two lines, and then remove myself from this
> discussion. You make C++ beginner's mistakes, which is totally ok, and
> can be overcome with a little training, but this is really not the place
> to discuss this, I'm afraid. I must apologize if I came across harsh at
> times, but you must understand that there's a gap between the level of
> questions you're asking and your ability to autonomously write correct
> C++ code, and I can't help you bridge that.
>
> void set_output_multiple (int tamano_entrada + nsimbolo);
>
> This doesn't really make sense. Either you're in a situation where you need 
> to supply the type (you *declare* or *define* the function/method 
> set_output_multiple), then your arguments must have types but need to be 
> identifiers and can not be expressions that give you a value (such as 
> tamano_entrada + nsimbolo).
>
> OR you're in a place to *use* that already existing function or method 
> (that's the case here), and the typename is wrong.
> I can't find any way that GCC won't give an error for this line, sorry; I 
> think you might be missing some compiler errors.
>
> void set_relative_rate (double relative_rate);
>
>
> That is **not** a call to gr::block::set_relative_rate. That is a function 
> declaration, possibly hiding the original method. C++ in some 
> compilers/versions supports local-scope function declarations like these. A 
> call would simply look like 
> set_relative_rate(12.12); 
> or
> set_relative_rate(relative_rate);
> but can *never* declare the type of either the arguments or the return value 
> of that function. That's logical, because the function must already be 
> declared if you want to use it. The fact that this seems to work better than 
> what I told you to do means that you have more mistakes that get hidden by 
> this mistake.
>
> Best regards,
> Marcus