(id bwp)
(role object)
(description "broken-weak-pair object [Chez Scheme]")

(id chezscheme)
(role directive)
(description "change to Chez Scheme read syntax")

(id compatible)
(role directive)
(description "R6RS+R7RS+keywords compatible syntax [Sagittarius]")

(id deprecated)
(role directive)
(description "display warning message of deprecated library [Sagittarius]")

(id eof)
(role object)
(description "end-of-file object [Chez Scheme, Chicken, Gambit, Kawa]")

(id false)
(role object)
(description "the boolean value false [R2RS, archaic]")

(id fold-case)
(role directive)
(description "change to case insensitive identifiers [R7RS]")

(id key)
(role keyword)
(description "start keyword arguments in lambda list [DSSSL, SRFI 89]")

(id larceny)
(role directive)
(description "implies #!no-fold-case and #!err5rs [Larceny]")

(id nocache)
(role directive)
(description "disable cache on the current loading file [Sagittarius]")

(id no-fold-case)
(role directive)
(description "change to case sensitive identifiers [R7RS]")

(id no-overwrite)
(role directive)
(description "deny overwriting exported variables [Sagittarius]")

(id null)
(role object)
(description "the empty list [R2RS, archaic]; Java null [Kawa]")

(id optional)
(role keyword)
(description "start optional arguments in lambda list [SRFI 89, MIT Scheme]")

(id err5rs)
(role directive)
(description "change to R7RS/R6RS syntax with extensions [Larceny]")

(id r5rs)
(role directive)
(description "change to R7RS syntax with #!fold-case [Larceny]")

(id r6rs)
(role directive)
(description "change to R6RS read syntax [R6RS]")

(id r7rs)
(role directive)
(description "change to R7RS syntax with #!no-fold-case [Gauche, Larceny, Sagittarius]")

(id read-macro)
(role directive)
(description "#!read-macro=name is the same as #<name> [Sagittarius]")

(id reader)
(role directive)
(description "#!reader=name replaces the reader with that library [Sagittarius]")

(id rest)
(role keyword)
(description "start rest argument in lambda list [SRFI 89, MIT Scheme]")

(id true)
(role object)
(description "the boolean value true [R2RS, archaic]")

(id void)
(role object)
(description "void object [Gambit, Kawa]")