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authorEli Barzilay <eli@barzilay.org>2013-07-16 01:22:48 -0400
committerEli Barzilay <eli@barzilay.org>2013-07-16 01:22:48 -0400
commitfa1ef10eddff3136ebaa38daae2646fdab81ca52 (patch)
treea9b186e7d52ca8fbe1f3fbb3b8f7311292b2ce05 /racket.html.markdown
parent4ad1441e839282f97fc3e2031f97a4adc552a707 (diff)
Remove spaces at end-of-lines.
Diffstat (limited to 'racket.html.markdown')
-rw-r--r--racket.html.markdown84
1 files changed, 42 insertions, 42 deletions
diff --git a/racket.html.markdown b/racket.html.markdown
index 25b92f62..fa20bf67 100644
--- a/racket.html.markdown
+++ b/racket.html.markdown
@@ -7,7 +7,7 @@ contributors:
---
-Racket is a general purpose, multi-paradigm programming language in the Lisp/Scheme family.
+Racket is a general purpose, multi-paradigm programming language in the Lisp/Scheme family.
Feedback is appreciated! You can reach me at [@th3rac25](http://twitter.com/th3rac25) or th3rac25 [at] [google's email service]
@@ -23,12 +23,12 @@ Feedback is appreciated! You can reach me at [@th3rac25](http://twitter.com/th3r
can span multiple lines and...
#|
they can be nested !
- |#
+ |#
|#
;; S-expression comments discard the following expression
#; "this expression will be discarded" "2nd expression" ; => "2nd expression"
-
+
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; 1. Primitive Datatypes and Operators
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
@@ -37,10 +37,10 @@ Feedback is appreciated! You can reach me at [@th3rac25](http://twitter.com/th3r
9999999999999999999999 ; integers
3.14 ; reals
6.02e+23
-1/2 ; rationals
-1+2i ; complex numbers
+1/2 ; rationals
+1+2i ; complex numbers
-;; Function application is written (f x y z ...)
+;; Function application is written (f x y z ...)
;; where f is a function and x, y, z, ... are operands
;; If you want to create a literal list of data, use ' to stop it from
;; being evaluated
@@ -56,16 +56,16 @@ Feedback is appreciated! You can reach me at [@th3rac25](http://twitter.com/th3r
(exact->inexact 1/3) ; => 0.3333333333333333
(+ 1+2i 2-3i) ; => 3-1i
-;;; Booleans
-#t ; for true
+;;; Booleans
+#t ; for true
#f ; for false -- any value other than #f is true
(not #t) ; => #f
(and 0 #f (error "doesn't get here")) ; => #f
(or #f 0 (error "doesn't get here")) ; => 0
-;;; Characters
+;;; Characters
#\A ; => #\A
-#\λ ; => #\λ
+#\λ ; => #\λ
#\u03BB ; => #\λ
;;; Strings are fixed-length array of characters.
@@ -111,7 +111,7 @@ some-var ; => 5
;; Structs
(struct dog (name breed age))
-(define my-pet
+(define my-pet
(dog "lassie" "collie" 5))
my-pet ; => #<dog>
(dog? my-pet) ; => #t
@@ -173,7 +173,7 @@ my-pet ; => #<dog>
(hash-ref m 'd 0) ; => 0
;; Use "hash-set" to extend a hash table
-(define m2 (hash-set m 'd 4))
+(define m2 (hash-set m 'd 4))
m2 ; => '#hash((b . 2) (a . 1) (d . 4) (c . 3))
;; Remember, these hashes are immutable!
@@ -186,7 +186,7 @@ m ; => '#hash((b . 2) (a . 1) (c . 3))
;; 3. Functions
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
-;; Use lambda to create new functions.
+;; Use lambda to create new functions.
;; A function always returns its last statement.
(lambda () "Hello World") ; => #<procedure>
@@ -201,14 +201,14 @@ m ; => '#hash((b . 2) (a . 1) (c . 3))
(define (hello-world2) "Hello World")
;; The () is the list of arguments for the function.
-(define hello
+(define hello
(lambda (name)
(string-append "Hello " name)))
(hello "Steve") ; => "Hello Steve"
;; You can have multi-variadic functions, too
(define hello2
- (case-lambda
+ (case-lambda
[() "Hello World"]
[(name) (string-append "Hello " name)]))
(hello2 "Jake") ; => "Hello Jake"
@@ -273,9 +273,9 @@ m ; => '#hash((b . 2) (a . 1) (c . 3))
[(list 0 _) 'fizz]
[(list _ 0) 'buzz]
[_ #f]))
-
+
(fizzbuzz? 15) ; => 'fizzbuzz
-(fizzbuzz? 37) ; => #f
+(fizzbuzz? 37) ; => #f
;;; Loops
@@ -283,9 +283,9 @@ m ; => '#hash((b . 2) (a . 1) (c . 3))
(define (loop i)
(when (< i 10)
(printf "i:~a~n" i)
- (loop (add1 i))))
+ (loop (add1 i))))
-(loop 5) ; => i:5 i:6 ...
+(loop 5) ; => i:5 i:6 ...
;; similarly, with a named let
(let loop ((i 0))
@@ -310,8 +310,8 @@ m ; => '#hash((b . 2) (a . 1) (c . 3))
;;; Sequences
-;; "for" allows iteration over sequences:
-;; lists, vectors, strings, sets, hash tables, etc...
+;; "for" allows iteration over sequences:
+;; lists, vectors, strings, sets, hash tables, etc...
(for ([i (in-list '(l i s t))])
(displayln i))
@@ -331,8 +331,8 @@ m ; => '#hash((b . 2) (a . 1) (c . 3))
;; To catch an exception, use the "with-handlers" form
;; To throw an exception use "raise"
-(with-handlers
- ([(lambda (v) (equal? v "infinity"))
+(with-handlers
+ ([(lambda (v) (equal? v "infinity"))
(lambda (exn) +inf.0)])
(raise "infinity"))
@@ -342,10 +342,10 @@ m ; => '#hash((b . 2) (a . 1) (c . 3))
;; Use set! to assign a new value to an existing variable
(define n 5)
-(set! n 6)
+(set! n 6)
n ; => 6
-;; Many Racket datatypes can be immutable or mutable
+;; Many Racket datatypes can be immutable or mutable
;; (Pairs, Lists, Strings, Vectors, Hash Tables, etc...)
;; Use "vector" to create a mutable vector
@@ -361,22 +361,22 @@ vec ; => #(1 2 3 4)
;; Modules let you organize code into multiple files and reusable libraries
(module cake racket/base ; define a new module 'cake' based on racket/base
-
+
(provide print-cake) ; function exported by the module
-
+
(define (print-cake n)
(show " ~a " n #\.)
(show " .-~a-. " n #\|)
(show " | ~a | " n #\space)
(show "---~a---" n #\-))
-
- (define (show fmt n ch) ;; internal function
+
+ (define (show fmt n ch) ;; internal function
(printf fmt (make-string n ch))
(newline)))
;; Use "require" to import all functions from the module
-(require 'cake)
-(print-cake 3)
+(require 'cake)
+(print-cake 3)
; (show "~a" 1 #\A) ; => error, "show" was not exported
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
@@ -385,24 +385,24 @@ vec ; => #(1 2 3 4)
;; Create a class fish%
(define fish%
- (class object%
+ (class object%
(init size) ; initialization argument
- (super-new) ; superclass initialization
+ (super-new) ; superclass initialization
; Field
- (define current-size size)
+ (define current-size size)
; Public methods
(define/public (get-size) current-size)
(define/public (grow amt) (set! current-size (+ amt current-size)))
(define/public (eat other-fish) (grow (send other-fish get-size)))))
;; Create an instance of fish%
-(define charlie
+(define charlie
(new fish% [size 10]))
;; Use "send" to call an object's methods
(send charlie grow 6)
(send charlie get-size) ; => 16
-
+
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; 9. Macros
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
@@ -421,14 +421,14 @@ vec ; => #(1 2 3 4)
(displayln i)
(set! i (add1 i))))
-;; Macros are hygienic, you cannot clobber existing variables!
+;; Macros are hygienic, you cannot clobber existing variables!
(define-syntax-rule (swap x y)
(begin
- (define tmp x)
+ (define tmp x)
(set! x y)
(set! y tmp)))
-(define tmp 1)
+(define tmp 1)
(define a 2)
(define b 3)
(swap a b)
@@ -444,7 +444,7 @@ vec ; => #(1 2 3 4)
(provide (contract-out
[deposit (-> positive? any)] ; amount will always be a positive number
[balance (-> positive?)]))
-
+
(define amount 0)
(define (deposit a) (set! amount (+ amount a)))
(define (balance) amount)
@@ -456,9 +456,9 @@ vec ; => #(1 2 3 4)
(balance) ; => 5
;; Any client that attempt to deposit a non-positive amount, will be blamed
-;; (deposit -5) ; => deposit: contract violation
+;; (deposit -5) ; => deposit: contract violation
;; expected: positive?
-;; given: -5
+;; given: -5
;; more details....
```