# Iteration 14: Here Documents
# === Basic here documents ===
=== simple here document
cat <<EOF
hello world
EOF
---
(command (word "cat") (redirect "<<" "hello world
"))
---
=== here document with multiple lines
cat <<END
line one
line two
line three
END
---
(command (word "cat") (redirect "<<" "line one
line two
line three
"))
---
=== here document empty
cat <<EOF
EOF
---
(command (word "cat") (redirect "<<" ""))
---
=== here document single line no newline at end
cat <<EOF
hello
EOF
---
(command (word "cat") (redirect "<<" "hello
"))
---
# === Different delimiters ===
=== delimiter with underscore
cat <<END_OF_DATA
content
END_OF_DATA
---
(command (word "cat") (redirect "<<" "content
"))
---
=== delimiter all caps
cat <<MARKER
text
MARKER
---
(command (word "cat") (redirect "<<" "text
"))
---
=== delimiter lowercase
cat <<end
text
end
---
(command (word "cat") (redirect "<<" "text
"))
---
=== delimiter mixed case
cat <<EndMarker
text
EndMarker
---
(command (word "cat") (redirect "<<" "text
"))
---
=== delimiter with numbers
cat <<EOF123
text
EOF123
---
(command (word "cat") (redirect "<<" "text
"))
---
# === Tab stripping with <<- ===
=== heredoc strip tabs
cat <<-EOF
indented with tab
EOF
---
(command (word "cat") (redirect "<<-" "indented with tab
"))
---
=== heredoc strip tabs multiple lines
cat <<-END
line one
line two
END
---
(command (word "cat") (redirect "<<-" "line one
line two
"))
---
=== heredoc strip tabs delimiter indented
cat <<-EOF
content
EOF
---
(command (word "cat") (redirect "<<-" "content
"))
---
# === Quoted delimiters (no expansion) ===
=== double quoted delimiter
cat <<"EOF"
$variable not expanded
EOF
---
(command (word "cat") (redirect "<<" "$variable not expanded
"))
---
=== single quoted delimiter
cat <<'EOF'
$variable not expanded
EOF
---
(command (word "cat") (redirect "<<" "$variable not expanded
"))
---
=== escaped delimiter
cat <<\EOF
$variable not expanded
EOF
---
(command (word "cat") (redirect "<<" "$variable not expanded
"))
---
=== partially quoted delimiter
cat <<E"OF"
$variable not expanded
EOF
---
(command (word "cat") (redirect "<<" "$variable not expanded
"))
---
# === Here documents with expansions ===
=== heredoc with variable
cat <<EOF
hello $name
EOF
---
(command (word "cat") (redirect "<<" "hello $name
"))
---
=== heredoc with command substitution
cat <<EOF
today is $(date)
EOF
---
(command (word "cat") (redirect "<<" "today is $(date)
"))
---
=== heredoc with arithmetic
cat <<EOF
result is $((1+2))
EOF
---
(command (word "cat") (redirect "<<" "result is $((1+2))
"))
---
=== heredoc with braced variable
cat <<EOF
value is ${var}
EOF
---
(command (word "cat") (redirect "<<" "value is ${var}
"))
---
# === Here documents in different positions ===
=== heredoc with other redirects
cat <<EOF >output.txt
content
EOF
---
(command (word "cat") (redirect "<<" "content
") (redirect ">" "output.txt"))
---
=== heredoc with fd number
cat 0<<EOF
content
EOF
---
(command (word "cat") (redirect "<<" "content
"))
---
=== heredoc after args
cat -n <<EOF
content
EOF
---
(command (word "cat") (word "-n") (redirect "<<" "content
"))
---
# === Multiple here documents ===
=== two here documents
cat <<EOF1 <<EOF2
first
EOF1
second
EOF2
---
(command (word "cat") (redirect "<<" "first
") (redirect "<<" "second
"))
---
# === Here document in pipelines ===
=== heredoc in pipeline
cat <<EOF | grep hello
hello world
goodbye world
EOF
---
(pipe (command (word "cat") (redirect "<<" "hello world
goodbye world
")) (command (word "grep") (word "hello")))
---
=== heredoc at end of pipeline
echo start | cat <<EOF
middle
EOF
---
(pipe (command (word "echo") (word "start")) (command (word "cat") (redirect "<<" "middle
")))
---
# === Here document in lists ===
=== heredoc with semicolon after
cat <<EOF; echo done
content
EOF
---
(semi (command (word "cat") (redirect "<<" "content
")) (command (word "echo") (word "done")))
---
=== heredoc with and
cat <<EOF && echo success
content
EOF
---
(and (command (word "cat") (redirect "<<" "content
")) (command (word "echo") (word "success")))
---
# === Here strings (<<<) ===
=== simple here string
cat <<<"hello world"
---
(command (word "cat") (redirect "<<<" ""hello world""))
---
=== here string with variable
cat <<<"$name"
---
(command (word "cat") (redirect "<<<" ""$name""))
---
=== here string unquoted
cat <<<hello
---
(command (word "cat") (redirect "<<<" "hello"))
---
# === Edge cases ===
=== heredoc delimiter on same line as content start
cat <<EOF
EOF
---
(command (word "cat") (redirect "<<" ""))
---
=== heredoc with blank lines
cat <<EOF
blank above and below
EOF
---
(command (word "cat") (redirect "<<" "
blank above and below
"))
---
=== heredoc with special characters in content
cat <<EOF
$dollar `backtick` "quotes" 'single'
EOF
---
(command (word "cat") (redirect "<<" "$dollar `backtick` "quotes" 'single'
"))
---
=== heredoc delimiter not at start of line does not end
cat <<EOF
not EOF here
EOF
---
(command (word "cat") (redirect "<<" "not EOF here
"))
---
# === Additional edge cases from research ===
=== heredoc with append redirect
cat <<EOF >>output.txt
content
EOF
---
(command (word "cat") (redirect "<<" "content
") (redirect ">>" "output.txt"))
---
=== heredoc with stderr redirect
cat <<EOF 2>&1
content
EOF
---
(command (word "cat") (redirect "<<" "content
") (redirect ">&" 1))
---
=== heredoc with or operator
cat <<EOF || echo failed
content
EOF
---
(or (command (word "cat") (redirect "<<" "content
")) (command (word "echo") (word "failed")))
---
=== heredoc with background operator
cat <<EOF &
content
EOF
---
(background (command (word "cat") (redirect "<<" "content
")))
---
=== heredoc in while loop body
while true; do cat <<EOF
hello
EOF
done
---
(while (command (word "true")) (command (word "cat") (redirect "<<" "hello
")))
---
=== heredoc in for loop body
for i in 1 2; do cat <<EOF
line
EOF
done
---
(for (word "i") (in (word "1") (word "2")) (command (word "cat") (redirect "<<" "line
")))
---
=== heredoc after if then
if true; then cat <<EOF
content
EOF
fi
---
(if (command (word "true")) (command (word "cat") (redirect "<<" "content
")))
---
=== heredoc with escaped dollar in content
cat <<EOF
price is \$100
EOF
---
(command (word "cat") (redirect "<<" "price is \$100
"))
---
=== heredoc with backslash at end of line
cat <<EOF
line continues\
next part
EOF
---
(command (word "cat") (redirect "<<" "line continuesnext part
"))
---
=== heredoc with only whitespace content
cat <<EOF
EOF
---
(command (word "cat") (redirect "<<" "
"))
---
=== heredoc strip tabs preserves spaces
cat <<-EOF
tab then spaces
EOF
---
(command (word "cat") (redirect "<<-" "tab then spaces
"))
---
=== heredoc delimiter with hyphen
cat <<END-MARKER
content
END-MARKER
---
(command (word "cat") (redirect "<<" "content
"))
---
=== herestring after file redirect
cat <input.txt <<<"extra"
---
(command (word "cat") (redirect "<" "input.txt") (redirect "<<<" ""extra""))
---
=== heredoc then herestring same command
cat <<EOF <<<"suffix"
prefix
EOF
---
(command (word "cat") (redirect "<<" "prefix
") (redirect "<<<" ""suffix""))
---
=== multiple commands after heredoc
cat <<EOF; echo one; echo two
content
EOF
---
(semi (semi (command (word "cat") (redirect "<<" "content
")) (command (word "echo") (word "one"))) (command (word "echo") (word "two")))
---
=== heredoc in subshell
(cat <<EOF)
content
EOF
---
(subshell (command (word "cat") (redirect "<<" "content
")))
---
=== heredoc in brace group
{ cat <<EOF; }
content
EOF
---
(brace-group (command (word "cat") (redirect "<<" "content
")))
---
=== heredoc with double backslash at end of line
cat <<EOF
test\\
next
EOF
---
(command (word "cat") (redirect "<<" "test\\
next
"))
---