Replace text between invisible markdown comments.

update_readme

#!/usr/bin/env bash

# This just replaces the text between a couple of hopefully invisible
# markdown comments, like so: `[//]: #` (text within backticks)

set -euo pipefail

main_output="$(cargo run -- --help)"
output="$(printf "### main\n\`\`\`\n%s\n\`\`\`" "$main_output")\n"
output+="### subcommands\n"
for subcmd in subcmd1 subcmd2; do
	subcmd_output="$(cargo run -- "$subcmd" --help)"
	output+="$(printf "#### %s\n\`\`\`\n%s\n\`\`\`" "$subcmd" "$subcmd_output")\n"
done
perl -i -pe "BEGIN{undef $/;} s@\[//\]: #\n.*\[//\]: #\$@[//]: #\n${output}[//]: #@smg" README.md