small improvements to style of examples on front page

This commit is contained in:
Matthias Felleisen 2014-03-12 13:35:34 -04:00
parent cd2b2f83bb
commit 5f11b06dc4

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@ -64,9 +64,9 @@
(generic-example #:title "Find Racket files" ; ----------------------------------------------- (generic-example #:title "Find Racket files" ; -----------------------------------------------
@code{#lang racket @code{#lang racket
;; Finds Racket sources in all subdirs ;; Finds Racket sources in all subdirs
(for ([path (in-directory)]) (for ([path (in-directory)]
(when (regexp-match? #rx"[.]rkt$" path) #:when (regexp-match? #rx"[.]rkt$" path))
(printf "source file: ~a\n" path)))} (printf "source file: ~a\n" path))}
@desc{The @elemcode{in-directory} function constructs a sequence that @desc{The @elemcode{in-directory} function constructs a sequence that
walks a directory tree (starting with the current directory, by default) walks a directory tree (starting with the current directory, by default)
and generates paths in the tree. The @elemcode{for} form binds and generates paths in the tree. The @elemcode{for} form binds
@ -97,11 +97,11 @@
(generic-example #:title "Unique Lines"; ----------------------------------------------- (generic-example #:title "Unique Lines"; -----------------------------------------------
@code{#lang racket @code{#lang racket
;; Report each unique line from stdin ;; Report each unique line from stdin
(let ([saw (make-hash)]) (define seen (make-hash))
(for ([line (in-lines)]) (for ([line (in-lines)])
(unless (hash-ref saw line #f) (unless (hash-ref seen line #f)
(displayln line)) (displayln line))
(hash-set! saw line #t)))} (hash-set! seen line #t))}
@desc{Uses a hash table to record previously seen lines. You can run this @desc{Uses a hash table to record previously seen lines. You can run this
program in DrRacket, but it makes more sense from the command line.})) program in DrRacket, but it makes more sense from the command line.}))
@; Additional examples: ------------------------------------------- @; Additional examples: -------------------------------------------
@ -110,10 +110,10 @@
@code{#lang racket ; A picture @code{#lang racket ; A picture
(require 2htdp/image) (require 2htdp/image)
(let sierpinski ([n 8]) (let sierpinski ([n 8])
(if (zero? n) (cond
(triangle 2 'solid 'red) [(zero? n) (triangle 2 'solid 'red)]
(let ([t (sierpinski (- n 1))]) [else (define t (sierpinski (- n 1)))
(freeze (above t (beside t t))))))} (freeze (above t (beside t t)))]))}
@desc{The @elemcode{2htdp/image} library provides easy-to-use functions @desc{The @elemcode{2htdp/image} library provides easy-to-use functions
for constructing images, and DrRacket can display an image result as for constructing images, and DrRacket can display an image result as
easily as it can display a number result. In this case, a easily as it can display a number result. In this case, a