On 7/10/18 6:44 AM, Ilkka Virta wrote:
> I think the problematic case here is when the number comes as input from
> some program, which might or might not print a leading sign or leading
> zeroes, but when we know that the number is, in any case, decimal.
>
> E.g. 'date' prints leading zeroes, which is easy enough to handle:
>
> hour=$(date +%H)
>
> hour=${hour#0} # remove one leading zero, or
> hour="10#$hour" # make it base-10
>
> The latter works even with more than one leading zero, but neither works
> with a sign. So, handling numbers like '-00159' gets a bit annoying:
That is not an integer constant. Integer constants don't begin with `-'.
Bash uses the same definition for constants as the C standard, with the
addition of the `base#value' syntax.
Since the `10#' notation is sufficient to deal with leading zeroes if you
want to force decimal, you only have to remove a leading unary plus or
minus.
--
``The lyf so short, the craft so long to lerne.'' - Chaucer
``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, UTech, CWRU c...@case.edu http://tiswww.cwru.edu/~chet/
