[r6rs-discuss] [Formal] Datum values, shared structure and eq? vs equal?

[Mikael Tillenius]

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Submitter: Mikael Tillenius mti at tillenius.com
Issue: Enhancement
Priority: Minor
Component: Formal Syntax
Version: 5.92
Summary: Datum values, shared structure and eq? vs equal?

Description: The description of datum values in section 1.9 doesn't 
forbidd shared structure. For example would the value of "(let ((x (cons 
(cons 1 2) 3))) (set-cdr! x (car x)) x)" return a datum value? I assume 
the answer i "no" but it would be nice to make it explicit. Also in 
section 3 (page 11, middle of right column) in the discussion of "(8 
13)" vs "( 8 13 )" I think it should be defined what is meant by 
"equal", by adding a reference to the predicate "equal?".

Proposal: Make it explicit in section 1.9 that shared or recursive 
structure is forbidden. Add a reference to "equal?" in section 9.6.

/Mikael