| Date: Sun, 25 Feb 2007 17:27:37 -0500 | From: John Cowan <[EMAIL PROTECTED]> | | William D Clinger scripsit: | | > The language described by the draft R6RS cannot be | > implemented by a pure interpreter (*). Lexical checking, | > macro expansion, syntax checking, bound-variable checking, | > and immutability checks are required before any part of a | > program can begin its execution. | | Are there any pure interpreters of Scheme? AFAIK, all of them | insist on reading at least one top-level form before executing | anything, and all do at least some preprocessing on that form.
Although it reads top-level expressions, SCM processes each sub-expression only the first time it is evaluated. So it has no distinct macro-expansion phase. Does that count as a "pure interpreter"? | There are languages like APL and Basic that have been implemented | by pure interpreters. _______________________________________________ r6rs-discuss mailing list [email protected] http://lists.r6rs.org/cgi-bin/mailman/listinfo/r6rs-discuss
