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Fixing pr11280

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This commit is contained in:
Jay McCarthy 2010-10-04 15:38:56 -06:00
parent 2f56b23b21
commit 09fbfcf5a9
15 changed files with 156 additions and 158 deletions
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52
collects/web-server/scribblings/tutorial/continue.scrbl
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@ -62,9 +62,9 @@ By the end of this tutorial, we'll have a simple blogging application.
We start by considering our data definitions. We want to represent a
list of posts. Let's say that a post is:
@racketblock[(define-struct post (title body))]
@racketblock[(struct post (title body))]
@(defstruct post ([title string?] [body string?]))
@(defstruct* post ([title string?] [body string?]))
@bold{Exercise.} Make a few examples of posts.
@ -75,8 +75,8 @@ A blog, then, will be a list of posts:
As a very simple example of a blog:
@racketblock[
(define BLOG (list (make-post "First Post!"
"Hey, this is my first post!")))
(define BLOG (list (post "First Post!"
"Hey, this is my first post!")))
]
Now that we have a sample blog structure, let's get our web
@ -172,7 +172,7 @@ an @racket[html-response] representing that content.
As an example, we want:
@racketblock[
(render-post (make-post "First post!" "This is a first post."))
(render-post (post "First post!" "This is a first post."))
]
to produce:
@ -229,8 +229,8 @@ should produce:
While
@racketblock[
(render-posts (list (make-post "Post 1" "Body 1")
(make-post "Post 2" "Body 2")))
(render-posts (list (post "Post 1" "Body 1")
(post "Post 2" "Body 2")))
]
should produce:
@ -441,9 +441,9 @@ Earlier, we had said that a @racket[blog] was a list of @racket[post]s,
but because we want to allow the blog to be changed, let's revisit our
definition so that a blog is a mutable structure:
@racketblock[(define-struct blog (posts) #:mutable)]
@racketblock[(struct blog (posts) #:mutable)]
@defstruct[blog ([posts (listof post?)])]
@defstruct*[blog ([posts (listof post?)])]
Mutable structures provide functions to change the fields of a
structure; in this case, we now have a structure mutator called
@ -484,7 +484,7 @@ the same blog.
Next, let's extend the application so that each post can hold a list
of comments. We refine the data definition of a blog to be:
@defstruct[post ([title string?] [body string?] [comments (listof string?)]) #:mutable]
@defstruct*[post ([title string?] [body string?] [comments (listof string?)]) #:mutable]
@bold{Exercise.} Write the updated data structure definition for posts. Make
sure to make the structure mutable, since we intend to add comments to
@ -504,7 +504,7 @@ comments in an itemized list.
@bold{Exercise.} Because we've extended a post to include comments, other
post-manipulating parts of the application may need to be adjusted,
such as uses of @racket[make-post]. Identify and fix any other part of the
such as uses of @racket[post]. Identify and fix any other part of the
application that needs to accommodate the post's new structure.
@centerline{------------}
@ -736,8 +736,8 @@ between the model of our blog, and the web application that uses that
model. Let's isolate the model: it's all the stuff near the top:
@racketblock[
(define-struct blog (posts) #:mutable)
(define-struct post (title body comments) #:mutable)
(struct blog (posts) #:mutable)
(struct post (title body comments) #:mutable)
(define BLOG ...)
(define (blog-insert-post! ...) ...)
(define (post-insert-comment! ...) ...)
@ -794,7 +794,7 @@ started running---which is exactly what we want when restoring the blog data fro
Our blog structure definition now looks like:
@racketblock[
(define-struct blog (posts) #:mutable #:prefab)
(struct blog (posts) #:mutable #:prefab)
]
Now @racket[blog] structures can be read from the outside world with @racket[read] and written
@ -809,7 +809,7 @@ At this point, we @emph{can} read and write the blog to disk. Now let's actually
First, we'll make a place to record in the model where the blog lives on disk. So, we need to change
the blog structure again. Now it will be:
@defstruct[blog ([home string?] [posts (listof post?)]) #:mutable]
@defstruct*[blog ([home string?] [posts (listof post?)]) #:mutable]
@bold{Exercise.} Write the new structure definition for blogs.
@ -820,14 +820,14 @@ Then, we'll make a function that allows our application to initialize the blog:
@code:comment{Reads a blog from a path, if not present, returns default}
(define (initialize-blog! home)
(local [(define (log-missing-exn-handler exn)
(make-blog
(blog
(path->string home)
(list (make-post "First Post"
"This is my first post"
(list "First comment!"))
(make-post "Second Post"
"This is another post"
(list)))))
(list (post "First Post"
"This is my first post"
(list "First comment!"))
(post "Second Post"
"This is another post"
(list)))))
(define the-blog
(with-handlers ([exn? log-missing-exn-handler])
(with-input-from-file home read)))]
@ -983,7 +983,7 @@ By adding a new comments table, we are more in accord with the relational style.
A @racket[blog] structure will simply be a container for the database handle:
@defstruct[blog ([db sqlite:db?])]
@defstruct*[blog ([db sqlite:db?])]
@bold{Exercise.} Write the @racket[blog] structure definition. (It does not need to be mutable or serializable.)
@ -993,7 +993,7 @@ We can now write the code to initialize a @racket[blog] structure:
@code:comment{Sets up a blog database (if it doesn't exist)}
(define (initialize-blog! home)
(define db (sqlite:open home))
(define the-blog (make-blog db))
(define the-blog (blog db))
(with-handlers ([exn? void])
(sqlite:exec/ignore db
(string-append
@ -1056,7 +1056,7 @@ However, we cannot tell from this structure
what blog this posts belongs to, and therefore, what database; so, we could not extract the title or body values,
since we do not know what to query. Therefore, we should associate the blog with each post:
@defstruct[post ([blog blog?] [id integer?])]
@defstruct*[post ([blog blog?] [id integer?])]
@bold{Exercise.} Write the structure definition for posts.
@ -1067,7 +1067,7 @@ The only function that creates posts is @racket[blog-posts]:
@code:comment{Queries for the post ids}
(define (blog-posts a-blog)
(local [(define (row->post a-row)
(make-post
(post
a-blog
(vector-ref a-row 0)))
(define rows (sqlite:select

8
collects/web-server/scribblings/tutorial/examples/dummy-3.rkt
View File

@ -3,17 +3,17 @@
;; A blog is a (make-blog db)
;; where db is an sqlite database handle
(define-struct blog (db))
(struct blog (db))
;; A post is a (make-post blog id)
;; where blog is a blog and id is an integer?
(define-struct post (blog id))
(struct post (blog id))
;; initialize-blog! : path? -> blog?
;; Sets up a blog database (if it doesn't exist)
(define (initialize-blog! home)
(define db (sqlite:open home))
(define the-blog (make-blog db))
(define the-blog (blog db))
(with-handlers ([exn? void])
(sqlite:exec/ignore db
(string-append
@ -35,7 +35,7 @@
;; Queries for the post ids
(define (blog-posts a-blog)
(local [(define (row->post a-row)
(make-post a-blog (string->number (vector-ref a-row 0))))
(post a-blog (string->number (vector-ref a-row 0))))
(define rows (sqlite:select
(blog-db a-blog)
"SELECT id FROM posts"))]

10
collects/web-server/scribblings/tutorial/examples/iteration-1.rkt
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@ -2,20 +2,20 @@
;; A blog is a (listof post)
;; and a post is a (make-post title body)
(define-struct post (title body))
(struct post (title body))
;; BLOG: blog
;; The static blog.
(define BLOG
(list (make-post "First Post" "This is my first post")
(make-post "Second Post" "This is another post")))
(list (post "First Post" "This is my first post")
(post "Second Post" "This is another post")))
;; start: request -> html-response
;; Consumes a request, and produces a page that displays all of the
;; web content.
(define (start request)
(render-blog-page BLOG request))
;; render-blog-page: blog request -> html-response
;; Consumes a blog and a request, and produces an html-response page
;; of the content of the blog.
@ -23,7 +23,7 @@
`(html (head (title "My Blog"))
(body (h1 "My Blog")
,(render-posts a-blog))))
;; render-post: post -> html-response
;; Consumes a post, produces an html-response fragment of the post.
(define (render-post a-post)

14
collects/web-server/scribblings/tutorial/examples/iteration-2.rkt
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@ -2,13 +2,13 @@
;; A blog is a (listof post)
;; and a post is a (make-post title body)
(define-struct post (title body))
(struct post (title body))
;; BLOG: blog
;; The static blog.
(define BLOG
(list (make-post "First Post" "This is my first post")
(make-post "Second Post" "This is another post")))
(list (post "First Post" "This is my first post")
(post "Second Post" "This is another post")))
;; start: request -> html-response
;; Consumes a request and produces a page that displays all of the
@ -21,7 +21,7 @@
[else
BLOG]))]
(render-blog-page a-blog request)))
;; can-parse-post?: bindings -> boolean
;; Produces true if bindings contains values for 'title and 'body.
@ -33,8 +33,8 @@
;; parse-post: bindings -> post
;; Consumes a bindings, and produces a post out of the bindings.
(define (parse-post bindings)
(make-post (extract-binding/single 'title bindings)
(extract-binding/single 'body bindings)))
(post (extract-binding/single 'title bindings)
(extract-binding/single 'body bindings)))
;; render-blog-page: blog request -> html-response
;; Consumes a blog and a request, and produces an html-response page
@ -49,8 +49,6 @@
(input ((name "body")))
(input ((type "submit")))))))
;; render-post: post -> html-response
;; Consumes a post, produces an html-response fragment of the post.
(define (render-post a-post)

20
collects/web-server/scribblings/tutorial/examples/iteration-3.rkt
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@ -2,25 +2,25 @@
;; A blog is a (listof post)
;; and a post is a (make-post title body)
(define-struct post (title body))
(struct post (title body))
;; BLOG: blog
;; The static blog.
(define BLOG
(list (make-post "First Post" "This is my first post")
(make-post "Second Post" "This is another post")))
(list (post "First Post" "This is my first post")
(post "Second Post" "This is another post")))
;; start: request -> html-response
;; Consumes a request and produces a page that displays all of the
;; web content.
(define (start request)
(render-blog-page BLOG request))
;; parse-post: bindings -> post
;; Extracts a post out of the bindings.
(define (parse-post bindings)
(make-post (extract-binding/single 'title bindings)
(extract-binding/single 'body bindings)))
(post (extract-binding/single 'title bindings)
(extract-binding/single 'body bindings)))
;; render-blog-page: blog request -> html-response
;; Consumes a blog and a request, and produces an html-response page
@ -33,16 +33,16 @@
,(render-posts a-blog)
(form ((action
,(make-url insert-post-handler)))
(input ((name "title")))
(input ((name "body")))
(input ((type "submit")))))))
(input ((name "title")))
(input ((name "body")))
(input ((type "submit")))))))
(define (insert-post-handler request)
(render-blog-page
(cons (parse-post (request-bindings request))
a-blog)
request))]
(send/suspend/dispatch response-generator)))
;; render-post: post -> html-response

24
collects/web-server/scribblings/tutorial/examples/iteration-4.rkt
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@ -2,25 +2,25 @@
;; A blog is a (make-blog posts)
;; where posts is a (listof post)
(define-struct blog (posts) #:mutable)
(struct blog (posts) #:mutable)
;; and post is a (make-post title body)
;; where title is a string, and body is a string
(define-struct post (title body))
(struct post (title body))
;; BLOG: blog
;; The initial BLOG.
(define BLOG
(make-blog
(list (make-post "First Post" "This is my first post")
(make-post "Second Post" "This is another post"))))
(blog
(list (post "First Post" "This is my first post")
(post "Second Post" "This is another post"))))
;; blog-insert-post!: blog post -> void
;; Consumes a blog and a post, adds the post at the top of the blog.
(define (blog-insert-post! a-blog a-post)
(set-blog-posts! a-blog
(cons a-post (blog-posts a-blog))))
;; start: request -> html-response
;; Consumes a request and produces a page that displays
;; all of the web content.
@ -30,8 +30,8 @@
;; parse-post: bindings -> post
;; Extracts a post out of the bindings.
(define (parse-post bindings)
(make-post (extract-binding/single 'title bindings)
(extract-binding/single 'body bindings)))
(post (extract-binding/single 'title bindings)
(extract-binding/single 'body bindings)))
;; render-blog-page: request -> html-response
;; Produces an html-response page of the content of the BLOG.
@ -43,15 +43,15 @@
,(render-posts)
(form ((action
,(make-url insert-post-handler)))
(input ((name "title")))
(input ((name "body")))
(input ((type "submit")))))))
(input ((name "title")))
(input ((name "body")))
(input ((type "submit")))))))
(define (insert-post-handler request)
(blog-insert-post!
BLOG (parse-post (request-bindings request)))
(render-blog-page request))]
(send/suspend/dispatch response-generator)))
;; render-post: post -> html-response

38
collects/web-server/scribblings/tutorial/examples/iteration-5.rkt
View File

@ -2,23 +2,23 @@
;; A blog is a (make-blog posts)
;; where posts is a (listof post)
(define-struct blog (posts) #:mutable)
(struct blog (posts) #:mutable)
;; and post is a (make-post title body comments)
;; where title is a string, body is a string,
;; and comments is a (listof string)
(define-struct post (title body comments) #:mutable)
(struct post (title body comments) #:mutable)
;; BLOG: blog
;; The initial BLOG.
(define BLOG
(make-blog
(list (make-post "First Post"
"This is my first post"
(list "First comment!"))
(make-post "Second Post"
"This is another post"
(list)))))
(blog
(list (post "First Post"
"This is my first post"
(list "First comment!"))
(post "Second Post"
"This is another post"
(list)))))
;; blog-insert-post!: blog post -> void
;; Consumes a blog and a post, adds the post at the top of the blog.
@ -52,22 +52,22 @@
,(render-posts make-url)
(form ((action
,(make-url insert-post-handler)))
(input ((name "title")))
(input ((name "body")))
(input ((type "submit")))))))
(input ((name "title")))
(input ((name "body")))
(input ((type "submit")))))))
;; parse-post: bindings -> post
;; Extracts a post out of the bindings.
(define (parse-post bindings)
(make-post (extract-binding/single 'title bindings)
(extract-binding/single 'body bindings)
(list)))
(post (extract-binding/single 'title bindings)
(extract-binding/single 'body bindings)
(list)))
(define (insert-post-handler request)
(blog-insert-post!
BLOG (parse-post (request-bindings request)))
(render-blog-page request))]
(send/suspend/dispatch response-generator)))
;; render-post-detail-page: post request -> html-response
@ -86,7 +86,7 @@
,(make-url insert-comment-handler)))
(input ((name "comment")))
(input ((type "submit")))))))
(define (parse-comment bindings)
(extract-binding/single 'comment bindings))
@ -94,8 +94,8 @@
(post-insert-comment!
a-post (parse-comment (request-bindings a-request)))
(render-post-detail-page a-post a-request))]
(send/suspend/dispatch response-generator)))

36
collects/web-server/scribblings/tutorial/examples/iteration-6.rkt
View File

@ -2,23 +2,23 @@
;; A blog is a (make-blog posts)
;; where posts is a (listof post)
(define-struct blog (posts) #:mutable)
(struct blog (posts) #:mutable)
;; and post is a (make-post title body comments)
;; where title is a string, body is a string,
;; and comments is a (listof string)
(define-struct post (title body comments) #:mutable)
(struct post (title body comments) #:mutable)
;; BLOG: blog
;; The initial BLOG.
(define BLOG
(make-blog
(list (make-post "First Post"
"This is my first post"
(list "First comment!"))
(make-post "Second Post"
"This is another post"
(list)))))
(blog
(list (post "First Post"
"This is my first post"
(list "First comment!"))
(post "Second Post"
"This is another post"
(list)))))
;; blog-insert-post!: blog post -> void
;; Consumes a blog and a post, adds the post at the top of the blog.
@ -52,22 +52,22 @@
,(render-posts make-url)
(form ((action
,(make-url insert-post-handler)))
(input ((name "title")))
(input ((name "body")))
(input ((type "submit")))))))
(input ((name "title")))
(input ((name "body")))
(input ((type "submit")))))))
;; parse-post: bindings -> post
;; Extracts a post out of the bindings.
(define (parse-post bindings)
(make-post (extract-binding/single 'title bindings)
(extract-binding/single 'body bindings)
(list)))
(post (extract-binding/single 'title bindings)
(extract-binding/single 'body bindings)
(list)))
(define (insert-post-handler request)
(blog-insert-post!
BLOG (parse-post (request-bindings request)))
(render-blog-page request))]
(send/suspend/dispatch response-generator)))
;; render-post-detail-page: post request -> html-response
@ -101,7 +101,7 @@
(define (back-handler request)
(render-blog-page request))]
(send/suspend/dispatch response-generator)))
;; render-confirm-add-comment-page :
@ -130,7 +130,7 @@
(define (cancel-handler request)
(render-post-detail-page a-post request))]
(send/suspend/dispatch response-generator)))
;; render-post: post (handler -> string) -> html-response

38
collects/web-server/scribblings/tutorial/examples/iteration-7.rkt
View File

@ -2,23 +2,23 @@
;; A blog is a (make-blog posts)
;; where posts is a (listof post)
(define-struct blog (posts) #:mutable)
(struct blog (posts) #:mutable)
;; and post is a (make-post title body comments)
;; where title is a string, body is a string,
;; and comments is a (listof string)
(define-struct post (title body comments) #:mutable)
(struct post (title body comments) #:mutable)
;; BLOG: blog
;; The initial BLOG.
(define BLOG
(make-blog
(list (make-post "First Post"
"This is my first post"
(list "First comment!"))
(make-post "Second Post"
"This is another post"
(list)))))
(blog
(list (post "First Post"
"This is my first post"
(list "First comment!"))
(post "Second Post"
"This is another post"
(list)))))
;; blog-insert-post!: blog post -> void
;; Consumes a blog and a post, adds the post at the top of the blog.
@ -52,22 +52,22 @@
,(render-posts make-url)
(form ((action
,(make-url insert-post-handler)))
(input ((name "title")))
(input ((name "body")))
(input ((type "submit")))))))
(input ((name "title")))
(input ((name "body")))
(input ((type "submit")))))))
;; parse-post: bindings -> post
;; Extracts a post out of the bindings.
(define (parse-post bindings)
(make-post (extract-binding/single 'title bindings)
(extract-binding/single 'body bindings)
(list)))
(post (extract-binding/single 'title bindings)
(extract-binding/single 'body bindings)
(list)))
(define (insert-post-handler request)
(blog-insert-post!
BLOG (parse-post (request-bindings request)))
(render-blog-page (redirect/get)))]
(send/suspend/dispatch response-generator)))
;; render-post-detail-page: post request -> html-response
@ -98,10 +98,10 @@
(parse-comment (request-bindings request))
a-post
request))
(define (back-handler request)
(render-blog-page request))]
(send/suspend/dispatch response-generator)))
;; render-confirm-add-comment-page :
@ -130,7 +130,7 @@
(define (cancel-handler request)
(render-post-detail-page a-post request))]
(send/suspend/dispatch response-generator)))
;; render-post: post (handler -> string) -> html-response

20
collects/web-server/scribblings/tutorial/examples/iteration-8.rkt
View File

@ -19,22 +19,22 @@
,(render-posts make-url)
(form ((action
,(make-url insert-post-handler)))
(input ((name "title")))
(input ((name "body")))
(input ((type "submit")))))))
(input ((name "title")))
(input ((name "body")))
(input ((type "submit")))))))
;; parse-post: bindings -> post
;; Extracts a post out of the bindings.
(define (parse-post bindings)
(make-post (extract-binding/single 'title bindings)
(extract-binding/single 'body bindings)
(list)))
(post (extract-binding/single 'title bindings)
(extract-binding/single 'body bindings)
(list)))
(define (insert-post-handler request)
(blog-insert-post!
BLOG (parse-post (request-bindings request)))
(render-blog-page (redirect/get)))]
(send/suspend/dispatch response-generator)))
;; render-post-detail-page: post request -> html-response
@ -65,10 +65,10 @@
(parse-comment (request-bindings request))
a-post
request))
(define (back-handler request)
(render-blog-page request))]
(send/suspend/dispatch response-generator)))
;; render-confirm-add-comment-page :
@ -97,7 +97,7 @@
(define (cancel-handler request)
(render-post-detail-page a-post request))]
(send/suspend/dispatch response-generator)))
;; render-post: post (handler -> string) -> html-response

20
collects/web-server/scribblings/tutorial/examples/model-2.rkt
View File

@ -2,25 +2,25 @@
;; A blog is a (make-blog home posts)
;; where home is a string, posts is a (listof post)
(define-struct blog (home posts) #:mutable #:prefab)
(struct blog (home posts) #:mutable #:prefab)
;; and post is a (make-post blog title body comments)
;; where title is a string, body is a string,
;; and comments is a (listof string)
(define-struct post (title body comments) #:mutable #:prefab)
(struct post (title body comments) #:mutable #:prefab)
;; initialize-blog! : path? -> blog
;; Reads a blog from a path, if not present, returns default
(define (initialize-blog! home)
(local [(define (log-missing-exn-handler exn)
(make-blog
(blog
(path->string home)
(list (make-post "First Post"
"This is my first post"
(list "First comment!"))
(make-post "Second Post"
"This is another post"
(list)))))
(list (post "First Post"
"This is my first post"
(list "First comment!"))
(post "Second Post"
"This is another post"
(list)))))
(define the-blog
(with-handlers ([exn? log-missing-exn-handler])
(with-input-from-file home read)))]
@ -41,7 +41,7 @@
(define (blog-insert-post! a-blog title body)
(set-blog-posts!
a-blog
(cons (make-post title body empty) (blog-posts a-blog)))
(cons (post title body empty) (blog-posts a-blog)))
(save-blog! a-blog))
;; post-insert-comment!: blog post string -> void

8
collects/web-server/scribblings/tutorial/examples/model-3.rkt
View File

@ -3,17 +3,17 @@
;; A blog is a (make-blog db)
;; where db is an sqlite database handle
(define-struct blog (db))
(struct blog (db))
;; A post is a (make-post blog id)
;; where blog is a blog and id is an integer?
(define-struct post (blog id))
(struct post (blog id))
;; initialize-blog! : path? -> blog?
;; Sets up a blog database (if it doesn't exist)
(define (initialize-blog! home)
(define db (sqlite:open home))
(define the-blog (make-blog db))
(define the-blog (blog db))
(with-handlers ([exn? void])
(sqlite:exec/ignore db
(string-append
@ -35,7 +35,7 @@
;; Queries for the post ids
(define (blog-posts a-blog)
(local [(define (row->post a-row)
(make-post
(post
a-blog
(vector-ref a-row 0)))
(define rows (sqlite:select

18
collects/web-server/scribblings/tutorial/examples/model.rkt
View File

@ -2,23 +2,23 @@
;; A blog is a (make-blog posts)
;; where posts is a (listof post)
(define-struct blog (posts) #:mutable)
(struct blog (posts) #:mutable)
;; and post is a (make-post title body comments)
;; where title is a string, body is a string,
;; and comments is a (listof string)
(define-struct post (title body comments) #:mutable)
(struct post (title body comments) #:mutable)
;; BLOG: blog
;; The initial BLOG.
(define BLOG
(make-blog
(list (make-post "First Post"
"This is my first post"
(list "First comment!"))
(make-post "Second Post"
"This is another post"
(list)))))
(blog
(list (post "First Post"
"This is my first post"
(list "First comment!"))
(post "Second Post"
"This is another post"
(list)))))
;; blog-insert-post!: blog post -> void
;; Consumes a blog and a post, adds the post at the top of the blog.

4
collects/web-server/scribblings/tutorial/examples/no-use-redirect.rkt
View File

@ -2,7 +2,7 @@
;; A roster is a (make-roster names)
;; where names is a list of string.
(define-struct roster (names) #:mutable)
(struct roster (names) #:mutable)
;; roster-add-name!: roster string -> void
;; Given a roster and a name, adds the name
@ -12,7 +12,7 @@
(append (roster-names a-roster)
(list a-name))))
(define ROSTER (make-roster '("kathi" "shriram" "dan")))
(define ROSTER (roster '("kathi" "shriram" "dan")))
;; start: request -> html-response
(define (start request)

4
collects/web-server/scribblings/tutorial/examples/use-redirect.rkt
View File

@ -2,7 +2,7 @@
;; A roster is a (make-roster names)
;; where names is a list of string.
(define-struct roster (names) #:mutable)
(struct roster (names) #:mutable)
;; roster-add-name!: roster string -> void
;; Given a roster and a name, adds the name
@ -12,7 +12,7 @@
(append (roster-names a-roster)
(list a-name))))
(define ROSTER (make-roster '("kathi" "shriram" "dan")))
(define ROSTER (roster '("kathi" "shriram" "dan")))
;; start: request -> html-response
(define (start request)