[plt-dev] Racket web page
On May 25, Danny Yoo wrote:
> ;; gets the unique lines, although not guaranteeing order:
> (let ([a-ht (for/fold ([a-ht #hash()])
> ([line (in-lines (current-input-port))])
> (hash-set a-ht line #t))])
> (for ([line (in-hash-keys a-ht)])
> (printf "~a~n" line)))
How about
#lang racket
(for ([line (in-list
(remove-duplicates
(sort (port->lines (current-input-port)) string<?)))])
(printf "~a\n" line))
> ;; nl: show line numbers along the side
> (for ([line (in-lines (current-input-port))]
> [no (in-naturals 1)])
> (printf "~a: ~a~n" no line))
>
> #lang racket
> ;; Compute md5 checksum of the file given at the command line
> (require scheme/cmdline
> file/md5)
> (printf "~a~n" (md5 (command-line #:args (filename) filename)))
Good points. (But what's with the old "~n"s?)
--
((lambda (x) (x x)) (lambda (x) (x x))) Eli Barzilay:
http://barzilay.org/ Maze is Life!