Hello,
It seems that ~r formatting function, when given a negative
number and a #:min-width argument, does not treat the "-"
character as part of the number bound by #:min-width,
and moreover, it detaches the "-" from the number:
> (~r -34.567 #:precision '(= 2) #:min-width 7)
"- 34.57"
As an example of a more expected behavior, see the
programs in C and Fortran:
#include <stdio.h>
int main (void)
{
printf("%7.2lf\n", -34.567);
}
PROGRAM TESTREAL
IMPLICIT REAL*8(x)
x = -34.567
write(*,100) '', x
100 format (A,F7.2)
END
both print " -34.57"
As another pro argument for the C/Fortran behavior: if one wanted
to detach "-" from the number, he would easily do
(string-append (if (negative? x) "-" "")
(~r (abs x) #:precision '(= 2) #:min-width 7)
while doing this thing backwards, i.e. attaching "-" to the
beginning of a space-padded number, is a more complicated task.
Are there any plans to get this functionality into ~r?
(or maybe it is already there and I do not know)
Best regards,
Dmitry
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