#!/bin/bash

{
  find . -name '*.ly' -exec sed '
    s/^.*\bifdef(`\([^'"'"']\+\)'"'"',.*$/\1/
    t
    d
  ' '{}' + \
  | sort -u \
  | sed '
    s/^STR_//
    t
    /^mit-/ p
    d
  '
} \
| sort -u \
| tr '\n' '-' \
| sed '
  s@-$@@
  s@^@-@
'