[r6rs-discuss] [Formal] Hashtable issues

[AndrevanTonder]

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Name        : Andre van Tonder
Email       : andre at het.brown.edu
Type        : 
Priority    : minor
Component   : Hashtables
Version     : 5.91
Pages       : 117
Dependencies: None

Summary:
--------

Minor issues in hashtable API.

Description:
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- In the rationale of hash-table-copy with immutable, it is stated that

     "Also, a library may choose to export a hash table which cannot be
      changed by clients."

   This may not be the best rationale, because it suggests that this is
   useful for access control that makes the table read-only to the client.
   However, the exporting "server" library won't be able to change the hash
   table copy either.  So "changed by clients" is misleading.

   Also, this has nothing to do with libraries, since any local
   scope can "export" a read-only hashtable by returning an immutable
   copy in this way.

- How often are "hash-table-keys" and "hash-table-values" really used, and
   even when they are, are they really a good abstraction?

   Since they are trivially expressible in terms of -fold, as stated in
   the document, please consider dropping these.