> Now to R6RS. Section 6.4 says that auxiliary syntax describes a syntax > binding. Section 12.4 of the R6RS Library Report defines `...' as auxiliary > syntax. The example definition of `case' in Section 12.5 ibid. shows > explicitely that auxiliary keywords are matched using `free-identifier=?' > (in this example, `else'). Also, in all other regards with respect to > auxiliary syntax R6RS does not differ from R7RS. >
P.S.: I just noticed that Guile does not export `...' from (rnrs base), which is an incompatiblity to the R6RS that is not mentioned by the following list, I think: https://www.gnu.org/software/guile/manual/html_node/R6RS-Incompatibilities.html#R6RS-Incompatibilities. Likewise, identifiers like `else' and `=>' are not exported by the Guile version of `(rnrs base)'. Oddly enough, other auxiliary syntax like `unquote' is being bound. It is probably enough to create the missing bindings around these lines in psyntax.scm: http://git.savannah.gnu.org/cgit/guile.git/tree/module/ice-9/psyntax.scm#n3230 and to export the bindings from `(guile)', `(rnrs base)', `(rnrs)', etc.
