Re: [PATCH] Document that $((expression)) is not portable.

[Ralf Wildenhues]

Hello Benoit,

* Benoit Sigoure wrote on Sun, Nov 11, 2007 at 06:48:45PM CET:
> 
> Wouldn't it be easier to list things that actually work on Solaris /bin/sh?
> :P

There was a time when people knew what to expect from a Bourne shell,
and what from a POSIX shell.  I guess.

> +
> +     Document that $((expression)) is not portable.
> +     * doc/autoconf.texi (Shell Substitutions): Here.
[...]

> address@hidden $((@var{expression}))
> address@hidden $((@var{expression}))
> +Arithmetic expansions are not considered portable as some shells (most
> +notably Solaris 10 @command{/bin/sh}) don't support them.

Fine with me, but why didn't you use singular here, too?  And why
"considered"?

  Arithmetic expansion is not portable as some shells (most
  notably Solaris 10 @command{/bin/sh}) don't support it.

I mean, two paragraphs up of your patch site, it already says:

| If you do use @samp{$(@var{commands})}, make sure that the commands
| do not start with a parenthesis, as that would cause confusion with
| a different notation @samp{$((@var{expression}))} that in modern
| shells is an arithmetic expression not a command.  To avoid the
| confusion, insert a space between the two opening parentheses.

Cheers,
Ralf