[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[Scheme-reports] diff between R6RS and the R7RS small language draft

The Scheme Steering Committee decided to split the upcoming standard
into two languages - a "small" language suitable for education,
research, embedded and extensions programming, and a "large" language
focused on the practical needs of mainstream software development.
The small language has a strong requirement of backwards compatibility
with R5RS and IEEE Scheme, while the large language is required to be
compatible with the R6RS while maintaining backwards compatibility
with the small language.

These are somewhat contradictory goals, but we are doing our best to
meet them.  Because of the R5RS compatibility requirement, and because
those interested in the small language are most likely to be familiar
with and favorable towards R5RS, the WG working on the small language
decided to base the new report directly on the R5RS, keeping the same
overall structure and borrowing ideas and text directly from the R6RS
where appropriate.  This helps ensure we meet our compatibility
requirements and also makes diffs shorter and easier to understand,
but increases the chances of our overlooking good changes made in
R6RS.  We encourage early readers to point out any missing R6RS
changes that seem appropriate for a small language, and keep in mind
that there will still be a large language upcoming which will include
many more features.

In light of this, the list of language changes in the draft are
described as a diff from R5RS.  We will also include a diff between
the small language and R6RS as a non-normative appendix.  An initial
version of this diff is available at:


Thank you,


Scheme-reports mailing list