Scheme's first-class continuation implemented with nested While loops

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2 pointssuzuki3 comments

A method to implement first-class continuation and call/cc (call-with-current-continuation) as found in Scheme is given in the article. The method uses nested "while" loops plainly and does not require the implementation language to be able to call functions recursively. Thus, it will be ported easily even to FORTRAN 77 if just given an automatic memory management of cons cells.

The current implementation runs in Emacs Lisp, Common Lisp, Lisps in Dart/TypeScript/Go and the implemented Lisp itself.

"Ported to Fortran 77" means, to me, that continuations can be captured across the activation frames of Fortran 77 functions. E.g. the interpreted Lisp code calls, say, a native mapcar written in F77 or whatever, passing it an interpreted function as the functional argument. The functional captures a continuation, right across the mapcar.

Sorry for my poor English. I meant it as implementing Scheme or some such interpreter with first-class continuation in FORTRAN77 by the method. One will be able to write mapcar in FORTRAN77, but in the same way as one write the IF special form of the interpreter.

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