Another reason for (perhaps) wanting an expression as a format
string:
Julia doesn't have a line continuation mechanism.
How does one split a long format string into parts without having
a string expression? The following doesn't work:
@sprintf("This is the first part of a rather long format string, which
I" *
"would like to extend onto %d (or maybe more) lines.", 5)
Thanks.
Cheers,
Ron
On Tuesday, December 2, 2014 8:40:56 PM UTC-5, Ronald L. Rivest wrote:
>
> I'm new to Julia, and got burned (aka wasted a fair amount of time)
> trying to sort out why @sprintf didn't work as I expected.
>
> julia> @sprintf("%2d",29)
> "29"
>
> julia> fmt = "%2d"
> "%2d"
>
> julia> @sprintf(fmt,29)
> ERROR: @sprintf: first argument must be a format string
>
> julia> @sprintf("%"*"2d",29)
> ERROR: @sprintf: first argument must be a format string
>
> I would expect that @sprintf would allow an arbitrary string expression as
> its
> format string. It obviously doesn't...
>
> There are many good reasons why one might want a format string expression
> instead
> of just a constant format string. For example, the same format may be
> needed in
> several places in the code, or you may want to compute the format string
> based on
> certain item widths or other alignment needs.
>
> At a minimum, this should (please!) be noted in the documentation.
>
> Better would be to have the extended functionality...
>
> (Or maybe it exists already -- have I missed something?)
>
> Thanks!
>
> Cheers,
> Ron Rivest
>
