Remove spaces from all elements of an array - arrays

Question

I've sample file named 'test.in' like below, with leading and trailing spaces:
Hi | hello how | are you?
I need | to remove | leading & trailing
spaces | where ever | it's located
I need to put the elements separated by "|" in array with "\n" as the main delimiter.
I want that each element in array shouldn't have leading or trailing spaces, only spaces in between characters are allowed. I'm using a sample code to test the results before I put the code is my primary deployment.
Portion of sample script:
OIFS="$IFS"
IFS=$'\n'
while read LINE
do
IFS='|'
my_tmpary=($LINE)
echo ${my_tmpary[#]}
my_ary=`echo ${my_tmpary[#]} | awk '$1=$1'`
echo ${my_ary[#]}
done < test.in
I would like NOT to use a loop to clean up the extra spaces.
I did trial & error methods using sed, awk, tr, but it's not a success for me yet.
my_ary[#] should be like this
Hi hello how are you?
I need to remove leading & trailing
spaces where ever it's located

Answer 1

You can (ab)use the fact that read will remove leading and trailing spaces when IFS is default:
while read -r line; do
printf "%s\n" "$line" # Leading and trailing spaces are removed.
done < test.in
Alternative you can sed for such task:
sed 's/^[[:space:]]*\|[[:space:]]*$//g' test.in

Answer 2

sed -E 's/[\t]{1,}/ /g;s/^ *| *$//g;s/[ ]{2,}/ /g;s/ *\| */ /g;' test.in
should do it. So :
$ my_ary=$(sed -E 's/[\t]{1,}/ /g;s/^ *| *$//g;s/[ ]{2,}/ /g;s/ *\| */ /g;' test.in)
$ echo "$my_ary"
Hi hello how are you?
I need to remove leading & trailing
spaces where ever it's located
This lines has many tabs
solves your problem.
Notes
1. s/[\t]{1,}/ /g converts the tabs ie \t to whitespaces.
2. s/^ *| *$//g removes the leading & trailing whitespaces.
3. s/[ ]{2,}/ /g squeezes multiple whitespaces to one.
4. s/ *\| */|/g removes the spaces around |
5. The -E enables the use of extended regex with sed.

Answer 3

In AWK:
awk '{gsub(/^ *| *$|/,"",$0); gsub(/ *\| *| +/," ",$0); print $0}' test.in
gsub(/^ *| *$|/,"",$0) remove leading and trailing space,
gsub(/ *\| *| +/," ",$0) replace space-pipe-space combos and multiple spaces with a single space,
print $0 print the whole record. $0 could be omitted like #mona_sax commented but for the sake of clarity I left it in code.
Surely it could be looped and each pipe delimited field trimmed separately:
awk -F\| -v OFS=" " ' # set input field separator to "|" and output separator to " "
function trim(str) {
gsub(/^ *| *$/,"",str); # remove leading and trailing space from the field
gsub(/ +/," ",str); # mind those multiple spaces as well
return str # return cleaned field
}
{
for(i=1;i<=NF;i++) # loop thru all pipe separated fields
printf "%s%s", trim($i),(i<NF?OFS:ORS) # print field and OFS or
} # output record separator in the end of record
' test.in
.