On 2006-11-01, Stephane CHAZELAS wrote:
> 2006-11-1, 02:56(-05), Chris F.A. Johnson:
>> On 2006-11-01, Stephane CHAZELAS wrote:
>>> 2006-10-31, 16:11(-08), Yakov:
>>>> I'm curious how to write the double "triangle" loop for $* in posix sh
>>>> analogous to this loop: for(k=0; k<N;k++) for(j=0; j<k; j++) body;
>>>> preferably in posix shell. I'm experienced shell scripter but here,
>>>> I'm stumped: for x in $*; do for y in ????; do body; done; done;
>>>> (???? must become the slice of $* list from $1 to one before
>>>> the element represented by $x)
>>>>
>>>> Is it possible at all ? bash-specific solutions are welcome, too,
>>>> but posix sh are preferred.
>>> [...]
>>>
>>> for x in $*
>>>
>>> is not correct.
>>
>> It may be correct. The OP may want it ...
> [...]
>
> It is syntactically correct but does not make any sense.

Of course it mase sense. It may not give the desired behaviour in
most cases, but it may well be what is wanted.

> It only makes sense (with the default value of IFS and setting of
> -f) if the positional parameters are to be taken as blank separated
> lists of file patterns, as in $1 == "*.txt foo*", $2 = "*.bar", and
> even then it's quite dangerous given the way the shells treat
> patterns that don't have any match.

The may be what is wanted, with or without set -f.

> With some other values of IFS, the behavior varies from shell to
> shell.
>
> With zsh (when not in sh or ksh mode),
>
> for x in $*
>
> loops over the non-empty positional parameters, a bit like in
>
> IFS=; set -f; for x in $*
>
> in some other shells.
>


--
Chris F.A. Johnson, author <http://cfaj.freeshell.org/shell>
Shell Scripting Recipes: A Problem-Solution Approach (2005, Apress)
===== My code in this post, if any, assumes the POSIX locale
===== and is released under the GNU General Public Licence