[r6rs-discuss] [Formal] Problems in description of instantiation semantics

[AndrevanTonder]

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Name        : Andre van Tonder
Email       : andre at het.brown.edu
Type        : defect
Priority    : medium
Component   : Libraries
Version     : 5.92
Pages       : 25-26
Dependencies: None

Summary:
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Library instantiation semantics insufficient or incorrect.

Description:
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The document does not distinguish evaluation times of macro definitions and 
variable definitions.  In particular, it states "An instance of a library 
corresponds to an evaluation of its definitions and expressions in a particular
phase relative to another library."

Given this, the following statement is incorrect:

   "... if the expanded form of one library references
   at phase 0 an identifier from another library, then
   before the referencing library is instantiated at phase n,
   the referenced library must be instantiated at phase n."

It is incorrect because it requires that macro definitions in the referenced 
library must be re-evaluated (unnecessarily) when the /already expanded/ 
referencing library is run.

Furthermore, the decription on pages 25-26 is incomplete.  It does not 
actually decribe the phase where the macro definitions in an imported must 
be evaluated (but the variable definitions must not).