Hi, thank you for creating SRFI-245! In Guile I enjoy it very much to be able to intersperse definitions and expressions.
The specification in SRFI-245 looks a bit too strict for me, though: > It is an error for the evaluation of any expression or of the > right-hand side of any definition in the sequence of definition or > expressions to require knowledge of the value of a variable whose > definition is to the right of it. Do I understand it correctly that this would mean that this would not work, because (define (using-later-procedure) (define x (y)) (define (y) #t) x) Or that it would stop to work if I interspersed logging messages? (define (using-later-procedure) (define x (y)) (display x)(newline) (define (y) #t) x) Both of these work in Guile, because Guile treats expressions before the final definition as implicit definitions: (define (using-later-procedure) (define x (y)) (define _1 (display x)) (define _2 (newline)) (define (y) #t) x) For details, see https://www.gnu.org/software/guile/manual/html_node/Internal-Definitions.html > (let () > (define a 1) > (foo) > (define b 2) > (+ a b)) > > is equivalent to > > (let () > (letrec* ((a 1) (_ (begin (foo) #f)) (b 2)) > (+ a b))) It may be useful to enforce an ordering between expressions and blocks of definitions, though, to ensure that logging code runs before the later definitions. Do I understand the letrec* implementation in the SRFI correctly that it would enforce the ordering of expressions before the directly following definition? Best wishes, Arne -- Unpolitisch sein heißt politisch sein, ohne es zu merken. draketo.de
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