Personally, I think the real problem here is the fact that macros take optional
parentheses. Your example seems like it should work, but it effectively was the
same as doing:
@printf(("%d,%d\n", 1, 2))
I've started always using parentheses with macros because it helps to avoid
some of these issues.
-- John
On Jun 11, 2014, at 7:45 PM, J Luis <[email protected]> wrote:
> Hmm, if it has to be, it has to be but the error message is really misleading.
>
> ... and BTW the manual example has a space
>
> @name (expr1, expr2, ...)
>
> Quinta-feira, 12 de Junho de 2014 3:26:39 UTC+1, Pontus Stenetorp escreveu:
> On 12 June 2014 11:06, J Luis <[email protected]> wrote:
> >
> > Hi, it took me a while and a good dose of swearing to figure this out
> >
> > julia> @printf ("%d,%d\n", 1,2)
> > ERROR: @printf: first or second argument must be a format string
> >
> > julia> @printf("%d,%d\n", 1,2)
> > 1,2
> >
> > The difference is only the space between the 'printf' and '('
> > Does it have to be like that? And can the error message be more correct?
>
> The issue is really with the way macros handle their arguments:
>
> http://julia.readthedocs.org/en/latest/manual/metaprogramming/#macros
>
> This in combination with the fact that `one(Int)` and `one (Int)` are
> equivalent, but `@printf("%d", 17)` and `@printf ("%d", 17)` are not.
> From my own naive stand-point I would vouch for disallowing spaces
> before the opening parenthesis for function calls a'la `one (Int)`.
> This, in my opinion, is bad style anyway. But perhaps I am missing
> some case where it would be useful.
>
> Regards,
> Pontus Stenetorp
