What problems are solved with R6RS Scheme's make-variable-transformer?

Posted by Michael Conner on Stack Overflow See other posts from Stack Overflow or by Michael Conner
Published on 2008-11-28T06:55:03Z Indexed on 2010/03/26 21:03 UTC
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Scheme

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macros

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syntax-case

While looking at the syntax-case section in R6RS, I saw the keyword make-variable-transformer, described as an identifier macro. The example given is very minimal, and I am not groking why it is necessary, or what use-cases require it. Finding additional examples of its use is also proving difficult. Presumably it makes some form of syntax transformation possible, or more elegant?

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