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Re: Moving ahead

This page is part of the web mail archives of SRFI 39 from before July 7th, 2015. The new archives for SRFI 39 contain all messages, not just those from before July 7th, 2015.

> Do you agree that what you are proposing violates the r5rs
> specification of delay?

Ouch...  I didn't think of the "possible" implementation given in
section 6.4:

  (delay <expression>)  ==>  (make-promise (lambda () <expression>))


  (define make-promise
    (lambda (proc)

This clearly prevents the DELAY form from capturing the dynamic
environment.  Programming languages should not be defined using an
implementation!!!  It specifies the semantics in more detail than is
given in the text (section 4.2.5).

So much for my grand plans for the proper semantics of DELAY
with respect to dynamic binding...