Aaron W. Hsu scripsit: > This is not clear to me. What about the dynamic extent in which the > thunk is evaluated? This affects parameters.
That's true, but it's a general problem which we have to resolve. What are we going to do about code like this: (define foo (make-parameter 0)) (define bar (delay (foo))) (parameterize ((foo 1)) (force bar)) Does this return 0, 1, or either? All the Schemes in my test suite that support SRFI 39 return 1. > Additionally, there is no > gain to forking a thread at force time, because force must wait for the > return any ways. No, the idea is for `delay` to fork a thread and `force` to join it (unless the result is already cached). > This is better done with the clearer and already existing futures > feature that some implementation have. I don't object to this, provided futures degenerate to promises if no parallel execution is possible. -- You annoy me, Rattray! You disgust me! John Cowan You irritate me unspeakably! Thank Heaven, [email protected] I am a man of equable temper, or I should http://www.ccil.org/~cowan scarcely be able to contain myself before your mocking visage. --Stalky imitating Macrea _______________________________________________ Scheme-reports mailing list [email protected] http://lists.scheme-reports.org/cgi-bin/mailman/listinfo/scheme-reports
