ECL currently implements the following specifications of the Common Lisp Document Repository:
| Number | Comments |
|---|---|
| 1 | In clos package; partial implementation, see Meta-Object Protocol (MOP) |
| 5 | In ext package |
| 7 | Only if ECL is compiled with --with-cmuformat configure option |
| 14 |
Table 3.2: Implemented CDR extensions