[plt-scheme] macro question

From: Matthias Felleisen (matthias at ccs.neu.edu)
Date: Tue Jun 10 12:22:56 EDT 2008

On Jun 10, 2008, at 11:40 AM, hendrik at topoi.pooq.com wrote:
> There are a few type inferences that do not seem to harm the
> readability of a program.  Type information can flow:
> (a) from the declaration of an identifier to its use
> (b) from the leaves of a parse tree towards its root (the usual
> direction of expressino evaluation)
> (c) from the root of a parse tree towards the leaves (called  
> coercion in
> Algol 68; a mechanism whereby the context of an expression affects its
> meaning.  Used for determining the types of initializers in C.

None of the above are considered 'type inference.' What you describe  
is the normal mode of type checking.

;; ---

> In my opinion, untyped Scheme needs to be built on top of typed  
> Scheme,
> not the other way around.  But until this revolution happens, I'm
> happy to use it they way it is.

NSF wasn't willing to fund a time machine, even when I promised I'd  
add cold fusion.

-- Matthias

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