[plt-dev] Racket web page

From: Sam Tobin-Hochstadt (samth at ccs.neu.edu)
Date: Wed May 26 12:42:04 EDT 2010

On Wed, May 26, 2010 at 12:34 PM, Jay McCarthy <jay.mccarthy at gmail.com> wrote:
> And I would recommend using hash-ref! to save a line.

#lang racket
;; Report each unique line from stdin:
(let ([saw (make-hash)])
  (for ([line (in-lines)])
    (hash-ref! saw line
      (λ () (displayln line)))))

sam th
samth at ccs.neu.edu

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