Earlier quoted context omitted.
Yes, I agree, that is a caricature. More seriously, I think leaning on this language-specific feature in a book that's supposedly teaching "general programming 101," or whatever, is in bad taste. As it says: > One reason that the distinction between process and procedure may be confusing is that most implementations of common languages (including Ada, Pascal, and C) are designed in such a way that the interpretation…
SICP point is that you can implement a for loop with tail recursion easily but not viceversa.
More importantly, in the listed languages (excepting a handful of compiler optimization options) the semantics of procedure calls are different than Scheme's semantics for procedure calls. So if you, in C, convert a for loop into a tail recursive procedure you have changed the behavior of the program, not just its appearance (and same in reverse). In Scheme or another language with tail call elimination, then this conversion ought not actually change the behavior of your program (done in either direction). This also has the effect of removing the loop constructs as a necessity of the language. You can describe an efficient iterative process in Scheme with tail recursion, but you cannot describe it (in a general sense, same caveat for some optimization options) with tail recursion in the listed procedural languages and must use a special syntax element (their loop constructs) to achieve the same program semantics.