[r6rs-discuss] [Formal] Treatment of literal keywords

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Name        : Andre van Tonder
Email       : andre at het.brown.edu
Type        : omission
Priority    : minor
Component   : Almost all components
Version     : 5.92
Pages       : 
Dependencies: None
Summary:
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It is not stated whether various literal keywords refer to bindings.
Description:
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It is unclear whether literal keywords such as unquote, =>, ..., _, else, 
protocol, fields, etc., refer to bindings, and if so, to what they are bound. 
Typically, such literals may be bound to a macro expanding to a syntax error, 
which is a good idea for error checking.
There is a very strong argument for requiring these literals to be bound.  If 
they refer to bindings, they can be exported, imported, prefixed, renamed, or 
excluded.  These are useful operations, and I think it is important for users 
to be able to rely on them to work portably.  Consider, for example, using 
syntax case together with a user-written matcher library, both of which use the 
identifiers ... and _ with separate meanings (here prefixing or renaming would 
be useful).
If it were decided that they do not refer to bindings, on the other hand, 
then they would be "always available" in the sense of the first paragraph of 
6.3, which should then be changed to reflect this (this would not, in my 
opinion, be a good thing, though).
Suggestion:
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Consider stating that literal identifiers refer to bindings, so that they can be 
imported/exported/renamed/excluded.