Re: text in programming languages, Unicode in strings

"Stephen Fuld" <SFuld@alumni.cmu.edu.invalid> writes:

And I miss some equivalent of picture clauses in C every time I see,
including in this NG, a number consisting of a string of say 8 or 9 or
more digits without the every three digit separator character, which
sure makes reading such numbers easier.  :-(

Why would you need a picture clause for that?  For output the Single
Unix Specification v3 specifies the flag "'" for printf(), which means
(from man 3 printf):

      For decimal conversion (i, d, u, f, F, g, G) the output is to be
      grouped with thousands' grouping characters if the locale infor‐
      mation  indicates any.  (See setlocale(3).)  Note that many ver‐
      sions of gcc(1) cannot parse this option and will issue a  warn‐
      ing.  (SUSv2 did not include %'F, but SUSv3 added it.)

You can also specify "'" in scanf():

       For decimal conversions, an optional quote character (').   This
       specifies  that  the input number may include thousands' separa‐
       tors as defined by the LC_NUMERIC category of  the  current  lo‐
       cale.   (See  setlocale(3).)  The quote character may precede or
       follow the '*' assignment-suppression character.

I am not convinced that the locale-specific input is a good idea, though.

Python3 supports _ as digit-group separator on input, and we have
implemented it in Gforth's development version, too.  For getting _ in
output from C programs with the feature above, I have created a locals
"prog": <https://www.complang.tuwien.ac.at/anton/locale-prog/>

- anton
--
'Anyone trying for "industrial quality" ISA should avoid undefined behavior.'
  Mitch Alsup, <c17fcd89-f024-40e7-a594-88a85ac10d20o@googlegroups.com>