awk: first, split a line into separate lines; second, use those new lines as a new input - awk

Question

Let's say I have this line:
foo|bar|foobar
I want to split it at | and then use those 3 new lines as the input for the further proceedings (let's say replace bar with xxx).
Sure, I can pipe two awk instances, like this:
echo "foo|bar|foobar" | awk '{gsub(/\|/, "\n"); print}' | awk '/bar/ {gsub(/bar/, "xxx"); print}'
But how I can achieve this in one script? First, do one operation on some input, and then treat the result as the new input for the second operation?
I tried something like this:
echo "foo|bar|foobar" | awk -v c=0 '{
{
gsub(/\|/, "\n");
sprintf("%s", $0);
}
{
if ($0 ~ /bar/) {
c+=1;
gsub(/bar/, "xxx");
print c;
print
}
}
}'
Which results in this:
1
foo
xxx
fooxxx
And thanks to the counter c, it's absolutely obvious that the subsequent if doesn't treat the multi-line input it receives as several new records but instead just as one multi-lined record.
Thus, my question is: how to tell awk to treat this new multi-line record it receives as many single-line records?
The desired output in this very example should be something like this if I'm correct:
1
xxx
2
fooxxx
But this is just an example, the question is more about the mechanics of such a transition.

Answer 1

I would suggest an alternative approach using split() where you can just split the elements based on the delimiter into an array and iterate over its fields, Instead of working on a single multi line string.
echo "foo|bar|foobar" |\
awk '{
count = 0
n = split($0, arr, "|")
for ( i = 1; i <= n; i++ )
{
if ( arr[i] ~ /bar/ )
{
count += sub(/bar/, "xxx", arr[i])
print count
print arr[i]
}
}
}'
Also you don't need an explicit increment of count variable, sub() returns the number of substitutions made on the source string. You can just increment to the existing value of count.
As one more level of optimization, you can get rid of the ~ match in the if condition and directly use the sub() function there
if ( sub(/bar/, "xxx", arr[i]) )
{
count++
print count
print arr[i]
}

Answer 2

If you set the record separator (RS) to the pipe character, you almost get the desired effect, e.g.:
echo 'foo|bar|foobar' | awk -v RS='|' 1
Output:
foo
bar
foobar
[...an empty line
Except that a new-line character becomes part of the last field, so there is an extra line at the end of the output. You can work around this by either including a new-line in the RS variable, making it less portable, or avoid sending new-lines to awk.
For example using the less portable way:
echo 'foo|bar|foobar' | awk -v RS='\\||\n' '{ sub(/bar/, "baz") } 1'
Output:
foo
baz
foobaz
Note that the empty record at the end is ignored.

Answer 3

With GNU awk:
$ awk -v RS='[|\n]' 'gsub(/bar/,"xxx"){print ++c ORS $i}' file
1
xxx
2
fooxxx
With any awk:
$ awk -F'|' '{c=0; for (i=1;i<=NF;i++) if ( gsub(/bar/,"xxx",$i) ) print ++c ORS $i }' file
1
xxx
2
fooxxx