| # Extract code block from a <details> section identified by data-file attribute. |
| # Usage: extract_code <file> <data-file> |
| # Example: extract_code ch01.md "main.cpp" |
| extract_code() { |
| local file="$1" name="$2" |
| local output |
| output=$(awk -v name="$name" ' |
| $0 ~ "data-file=\"" name "\"" { found=1; next } |
| found && /^```/ && !inside { inside=1; next } |
| inside && /^```/ { exit } |
| inside { print } |
| ' "$file") |
| if [ -z "$output" ]; then |
| echo "ERROR: extract_code: no match for data-file=\"$name\" in $file" >&2 |
| return 1 |
| fi |
| printf '%s\n' "$output" |
| } |
