correct way to create boiler plate code

[Timon Gehr]

> I am parsing some formulas from a spreadsheet file. To duplicate
> the behavior of the spreadsheet functions, I am having to create a
> lot of boiler plate code that maps from the spreadsheet functions
> to the built-in functions. Mixin would seem to allow me to
> automate the boiler-plate creation, but i am not utilizing it
> correctly. What is the correct to call Mixin in this situation, or
> is their a better way to create the boiler-plate code?
>
> For background, i am new to D. D is my second language with my
> primary experience being a script kiddie in Excel VBA, so take it
> slow, please.

hi,

Disregard the other answer, making func immutable won't solve your problem.

> string[] funcs = ["tan"];
> void createFuncs(){
>  foreach(func; funcs){
>   mixin("double " ~ toupper(func) ~ "(double aReal)
> {return(" ~ func ~ "(aReal));}");
>  }
> }


foreach runs at runtime, while mixin is expanded at compile time.

If you want to inject your boilerplate into module namespace, you would rather
write a function that generates the code and mixin the result of a call to that
function:

string[] funcs = ["tan"];
string createFuncs(){
  string res;
  foreach(func; funcs){
    res~="double " ~ toupper(func) ~ "(double aReal){return(" ~ func ~ "(aReal));}";
  }
  return res;
}
mixin(createFuncs());