[plt-scheme] %, @, ^, etc.

From: Felix Klock's plt proxy (pltscheme at pnkfx.org)
Date: Mon Sep 8 19:22:03 EDT 2003

On Monday, September 8, 2003, at 05:06 PM, Matthew Flatt wrote:
> Any more?

I've begun using the convention of appending two exclamation points to 
procedures that return mutators as higher order procedures.

For example,
(define make-counter!!
    (lambda (init)
        (let ((cell init))
            (lambda (new-val)
                  (begin0 cell (set! cell new-val))))))

(define count-a! (make-counter!! 0))
(define count-b! (make-counter!! 0))

I haven't actually decided if I like this notation or not.  But I 
thought that a notation for this sort of pattern is sorely missing.

-Felix (who was very upset to discover that his pltscheme address has 
been leaked to a spam mailer, and would be curious to know if any other 
plt-scheme'rs using a similar technique to isolate sources of spam have 
recently encountered spam from "Robert Seviour" 
<SFESeminarsLtd at totalise.co.uk>)

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