Re: function overloading - Mailing list pgsql-general

From Tom Lane
Subject Re: function overloading
Date
Msg-id 7740.1136838516@sss.pgh.pa.us
Whole thread Raw
In response to function overloading  (Robert Greimel <greimel@ing.iac.es>)
Responses Re: function overloading  (Robert Greimel <greimel@ing.iac.es>)
List pgsql-general
Robert Greimel <greimel@ing.iac.es> writes:
> I have a question regarding function overloading:

> assume that you have a function that takes several numeric arguments -
> lets for example say 4 arguments: f(a,b,c,d)

> Now further assume that internally in the function the first thing you
> do is to convert the arguments to double precision, do your calculations
> and return the result always in double precision.

> In order to allow for all combinations of numeric
> (int2,int4,int8,float4,float8) inputs one would now have to define and
> write 5^4 = 625 functions !!!!!!!!!!!!!!!

> Apart from forcing the function user to use casts, is there any other
> way to avoid this madness of writing 625 functions ?

I don't see why you need more than one function, taking all
double-precision arguments ...

            regards, tom lane

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