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Re: [Scheme-reports] Identifiers imported "by reference or value"?

Related to this is one paragraph in 5.1:

It says:

Import declarations and definitions cause bindings to be
created in the global environment or modify the value of
existing global bindings. The initial environment of a pro-
gram is empty, so at least one import declaration is needed
to introduce initial bindings.

  [..] it is an error to import the same identifier more than once with
  different bindings, or to redefine or mutate an imported binding with
  a definition or with set!

The order of the import and definition don't matter.  Section
5.6.1 specifically lists two possible implementations of
libraries, in one of which all imports are performed before
the expressions from begin and include are expanded.

Great! This means that my problematic example does not work, which is good.

Which leaves the question to which situations the possibility of modifying an existing global binding as mentioned in the quoted paragraph from 5.1. actually applies.

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