"CPL was so new that it had no compiler, nor a complete formal description. Journal articles from 1963 and 1968 and a posthumously published set of notes from 2000 partially describe versions of the language that are slightly different than the one presented in the article."
Apparently a formal definition was finally written down in "CPL working papers", but this was never published. The only place I know which has a copy is the Bodleian library at Oxford:
This makes CPL seem like a pretty odd choice of language for such a widely-read magazine article. He couldn't have expected his readers to be familiar with it, especially since the language was still changing at the time. Did he think it was close enough to pseudo-code that it was ok?
Readers at the time would have expected to do somewhat more work to understand a program; ASCII had only recently been standardised, so even programs in the same language would have slightly different syntax, depending on the computer they were written for (also see stropping: http://en.wikipedia.org/wiki/Stropping_%28programming%29 ).
But fundamentally, he was the designer and major promoter of CPL.
Apparently a formal definition was finally written down in "CPL working papers", but this was never published. The only place I know which has a copy is the Bodleian library at Oxford:
http://www.nationalarchives.gov.uk/a2a/records.aspx?cat=161-...
It would be a good thing if someone (google?) were to scan this piece of computer history and put it on the web.