[plt-scheme] transformer environment and identifier-binding

From: Doug Orleans (dougo at place.org)
Date: Mon May 3 23:42:52 EDT 2004

Matthew Flatt writes:
 > At Sun, 21 Mar 2004 02:53:46 -0500, Doug Orleans wrote:
 > > This is a contrived example, but I'm running into this problem when
 > > using `syntax-case' in a required-for-syntax module: it can't detect
 > > `lambda' in a syntax object, because it's not `module-identifier=?' to
 > > the `lambda' that appears in the literal list (because that `lambda'
 > > is a free identifier).  If I copy the `syntax-case' expression directly
 > > into the transformer expression, it works fine, but isn't the point of
 > > `require-for-syntax' that I should be able to put it into a module
 > > instead?
 > This is a common problem. When an imported function needs to compare
 > identifiers to some constant, one option is to pass the constant into
 > the helper function (because the caller has a suitable binding).

I was thinking about doing this, but doesn't this mean I can't use
`syntax-case'?  It requires the constant identifiers to be provided
inline.  I think what I really need is something like
`module-identifier=module-transformer-identifier?' but I have no idea
how to write it...

--dougo at place.org

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