## online literature on CPL?

Hello all!

Is there available online (and free) literature on CPL? More specifically, I am interested in
D.W. Barron, J.N. Buxton, D.F. Hartley, E. Nixon, C. Strachey. The main features of CPL. The Computer Journal, Vol.6, #2, pp.134-143 (1963)'
and
D.W. Baron, C. Strachey. Programming. In L. Fox, ed. Advances in Programming and Non-numerical Computation, pp.49-82. Pergammon Press, 1966'.
So far, the only source I was able to find is this volume in commemoration of Chrostopher Strachey, but even there they seem to have pulled off the full texts already.

Boyko

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### Thanks, but that does not

Thanks, but that does not work for me. All the links (including those to cached pages) eventually lead to non-existing files.

### Yes, I mean the Common

Yes, I mean the Common Programming Language developed by Strachey and colleagues in the 1960s.

### Strachey on CPL

I happened to notice that Strachey mentions CPL in the comments in the back of Landin's "The Next 700 Programming Languages" (1965). Strachey says:

I must just interpolate here something which is a bit of advertising I suppose. Nearly all the linguistic features, such as 'where' and 'while' and 'and' and 'recursive', that Peter Landin has been talking about are incorporated as an integral part of a programming language being developed at Cambridge and London called CPL. In fact the 'where' clauses are a very important feature of this language.

CPL seems to have had proper closures, judging by later remarks and of course the comparison to Landin's ISWIM.

Strachey goes on to give a rather prescient analysis of the benefits, prospects and challenges for functional languages, which he calls descriptive or declarative languages, aka DLs. He also talks about the issues of adding imperative features to such languages,

Then CPL inspired BCPL (Basic CPL), which removed "those features of the full language which make compilation difficult" (from Wikipedia). It looks as though full closures may have been one such feature. BCPL inspired C, which removed further features such as the ability to define nested functions.

So we ended up with C because of some of the technical challenges with implementing functional languages. The exact moment in history where it all went wrong... ;)