Shell style for multi-stage pipeline with heredoc

[robin-a-meade]

Please update the Shell Style guide to indicate which of the following 3 approaches for a multi-stage pipeline with heredoc is recommended:

Approach 1

cat <<'EOF' \
| cat \
| cat \
| cat
hello
EOF

Approach 2

cat <<'EOF' |
hello
EOF
cat \
| cat \
| cat

Approach 3

(
  cat \
  | cat \
  | cat \
  | cat 
) <<'EOF'
hello
EOF

Discussion: https://stackoverflow.com/questions/7046381