如何选择特定的行并在bash shell的末尾回显

Question

How can I take specific lines from pipeline and then echo them at the end. To show what I mean - I have few lines sent through pipeline and proccesing like this

#!bin/bash   
 while read line; do
 echo "$line"
done

I have this input

foo1 -> long
foo1 -> hell
foo1 -> fail
foo1
fast1 -> fine
fast1 -> good
fast1

I need to do this

foo1 -> long
foo1 -> hell
foo1 -> fail
fast1 -> fine
fast1 -> good
fast1
foo1

Just an example - there would be much longer input to process

Answer 1

You can use BASH array to store certain lines in array to be printed later:

lines=()
while read line; do
 if [[ $someCondition ]]; then
   lines+=("$line")
 else
   echo "$line"
 fi
done

# print array now:
printf "%s\n" "${lines[@]}"