[Rcpp-devel] Picking off a matrix-valued list element inside a class constructor?

[Darren Cook]

>         Rcpp::IntegerMatrix m = l["m"];;
> ...
> This seems to work just fine.
> ... the seemingly equivalent statement in the body of a class
> constructor fails with a compilation error:
> ...
>     CCC(Rcpp::List l){
>       m = l["m"];
>     }


In C++, the left side can sometimes give a hint about how the right-side
should be interpreted. When I changed the constructor body to this it
worked:
   Rcpp::IntegerMatrix tmp=l["m"];
   m = tmp;

I tried a few ideas to get a one-liner that does the same... and
couldn't; perhaps someone else knows the magic syntax?

(For reference these were what I tried:
   m =Rcpp::IntegerMatrix(l["m"]);
   m =(Rcpp::IntegerMatrix)l["m"];
   m.operator=<Rcpp::IntegerMatrix>(l["m"]);
)

>   [...]
>   private:
>     Rcpp::IntegerMatrix m;
>   }   <-- NEED SEMI-COLON HERE
>   '

BTW, you are missing a semi-colon after the closing bracket for your class.

Darren

-- 
Darren Cook, Software Researcher/Developer

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