Hi,

I have this little script that sets up two lines in BASIC (or whatever
data made by a couple number/text), and put the data in an array element
whose index is the number and whose argument is the text:

-- BEGIN script --

# set first line, intentionally the second
ln=10
pr="PRINT I"
prog[$ln]="$pr"

# set second line, which is the first
ln=5
pr="REM PROVA"
prog[$ln]="$pr"

# list lines in order - print only the text, for now!
for i in "${prog[@]}"; do
printf "%s\n" "$i"
done

-- END script --

How can I access the inner index (here 5 and 10) to print along the $i
content and change the printf to

printf "%d %s" <what?> "$i"

?

Thanks

-- Antonio

On 2006-12-10, Antonio Maschio wrote:
> Hi,
>
> I have this little script that sets up two lines in BASIC (or whatever
> data made by a couple number/text), and put the data in an array element
> whose index is the number and whose argument is the text:
>
> -- BEGIN script --
>
> # set first line, intentionally the second
> ln=10
> pr="PRINT I"
> prog[$ln]="$pr"
>
> # set second line, which is the first
> ln=5
> pr="REM PROVA"
> prog[$ln]="$pr"
>
> # list lines in order - print only the text, for now!
> for i in "${prog[@]}"; do
> printf "%s\n" "$i"
> done

The loop is unnecessary if all you want to do is print the members
of the array:

printf "%s\n" "${prog[@]}"


> -- END script --
>
> How can I access the inner index (here 5 and 10) to print along the $i
> content and change the printf to
>
> printf "%d %s" <what?> "$i"
>
> ?

n=0
i=0
while [ "$n" -lt "${#prog[@]}" ]
do
if [ -n "${prog[$i]}" ]
then
printf "%d %s\n" "$i" "${prog[$i]}"
n=$(( $n + 1 ))
fi
i=$(( $i + 1 ))
done

--
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

Chris F.A. Johnson <cfajohnson@gmail.com> wrote:
> On 2006-12-10, Antonio Maschio wrote:
>> Hi,
>>
>> I have this little script that sets up two lines in BASIC (or whatever
>> data made by a couple number/text), and put the data in an array element
>> whose index is the number and whose argument is the text:

[ prog[5]="REM PROVA" ; prog[10]="PRINT I"
for i in "${prog[@]}" ; do printf '%s\n' "$i" ; done ]

>> How can I access the inner index (here 5 and 10) to print along the $i
>> content and change the printf to
>>
>> printf "%d %s" <what?> "$i"
>>
>> ?
>
> n=0
> i=0
> while [ "$n" -lt "${#prog[@]}" ]
> do
> if [ -n "${prog[$i]}" ]

if [ "${prog[$i]+x}" = "x" ] # to handle empty elements (prog[7]="")

> then
> printf "%d %s\n" "$i" "${prog[$i]}"
> n=$(( $n + 1 ))
> fi
> i=$(( $i + 1 ))
> done

To the OP: Bash (as of version 3.0) and ksh93 can list array indices:

for i in "${!prog[@]}" ; do
printf '%d %s\n' "$i" "${prog[$i]}"
done