Re: [racket] Ensuring data fed to web-server/templates is textual
A few minutes ago, Jay McCarthy wrote: > On Thu, Feb 9, 2012 at 12:19 PM, Eli Barzilay wrote: > > Yesterday, Jay McCarthy wrote: > >> web-server/templates uses scribble/text > >> > >> So, if you return a function, then it will be called. > >> > >> We could also change scribble/text to support a struct/class > >> property for JIT transformation. Does that sound good? > >> > >> Is that okay with you, Eli? > > > > Why a property? There is already a `with-writer' that can be used to > > apply a custom writer, and that's how `scribble/html' does things. > > I see no docs for with-writer or scribble/html, so I don't know what > these are. No docs becasue I don't have a good API yet, so it's still a kind of a private backdoor. (And that's what I'd like to change.) > > (And going back to the property, if you're looking for a way to do > > this for some particular value, then the right way to do this is > > to use the procedure property -- the text outputter treats > > anything that looks as a thunk by applying it to get the value to > > actually put out.) > > Ya, the procedure property sounds like the way to go. OK. (I was hoping that there's a need for an organized writer thing to sort out the above...) -- ((lambda (x) (x x)) (lambda (x) (x x))) Eli Barzilay: http://barzilay.org/ Maze is Life! Racket Users list: http://lists.racket-lang.org/users
Re: [racket] Ensuring data fed to web-server/templates is textual
On Thu, Feb 9, 2012 at 12:19 PM, Eli Barzilay wrote: > Yesterday, Jay McCarthy wrote: >> web-server/templates uses scribble/text >> >> So, if you return a function, then it will be called. >> >> We could also change scribble/text to support a struct/class >> property for JIT transformation. Does that sound good? >> >> Is that okay with you, Eli? > > Why a property? There is already a `with-writer' that can be used to > apply a custom writer, and that's how `scribble/html' does things. I see no docs for with-writer or scribble/html, so I don't know what these are. > > But that feature is not really great, IMO, and I really want to get > something better instead -- something where I can compose a bunch of > writers (in a form of input-regexp, output-string), disable some, > etc. If anyone is interested in trying to get something here I'd be > happy to provide more details. > > (And going back to the property, if you're looking for a way to do > this for some particular value, then the right way to do this is to > use the procedure property -- the text outputter treats anything that > looks as a thunk by applying it to get the value to actually put out.) Ya, the procedure property sounds like the way to go. Jay -- Jay McCarthy Assistant Professor / Brigham Young University http://faculty.cs.byu.edu/~jay "The glory of God is Intelligence" - D&C 93 Racket Users list: http://lists.racket-lang.org/users
Re: [racket] Ensuring data fed to web-server/templates is textual
On Thu, Feb 9, 2012 at 11:45 AM, Jordan Johnson wrote: > > On Feb 8, 2012, at 10:17 AM, Jay McCarthy wrote: > web-server/templates uses scribble/text >> >> So, if you return a function, then it will be called. > > I'm not sure I understand the implication: that I could achieve what I'm > after by wrapping the images in a function? I'm not clear on how that would > work. If a template includes a function, then the function gets called to produce the value to display. So rather than having "image" you'd have "(lambda () (convert-to-what-i-want image))" > >> We could also change scribble/text to support a struct/class property >> for JIT transformation. Does that sound good? > > This sounds like it might be the kind of thing I'm after. Given that I don't > necessarily know how the images are being created, could attaching such a > property be done without changing how the image%s are instantiated? > > Thanks, > Jordan > >> Is that okay with you, Eli? >> >> Jay >> >> On Tue, Feb 7, 2012 at 4:50 PM, Jordan Johnson wrote: >>> Hi all, >>> >>> I'm using web-server/templates to generate text, and the data in variables >>> I reference in the template include s-exps that may, in some cases, contain >>> image% objects. I want it to render the image%s as plain text; even just >>> the string "" or similar would be adequate. >>> >>> So, my question is: how (via the template system or other libraries) can I >>> best make racket perform this translation, ideally without writing code to >>> walk the s-exp trees? It seems there must be a way someplace to tweak the >>> output function used by the template library, but I don't know where that >>> would be. >>> >>> Best, >>> Jordan >>> >>> Racket Users list: >>> http://lists.racket-lang.org/users >> >> >> >> -- >> Jay McCarthy >> Assistant Professor / Brigham Young University >> http://faculty.cs.byu.edu/~jay >> >> "The glory of God is Intelligence" - D&C 93 -- Jay McCarthy Assistant Professor / Brigham Young University http://faculty.cs.byu.edu/~jay "The glory of God is Intelligence" - D&C 93 Racket Users list: http://lists.racket-lang.org/users
Re: [racket] Ensuring data fed to web-server/templates is textual
Yesterday, Jay McCarthy wrote: > web-server/templates uses scribble/text > > So, if you return a function, then it will be called. > > We could also change scribble/text to support a struct/class > property for JIT transformation. Does that sound good? > > Is that okay with you, Eli? Why a property? There is already a `with-writer' that can be used to apply a custom writer, and that's how `scribble/html' does things. But that feature is not really great, IMO, and I really want to get something better instead -- something where I can compose a bunch of writers (in a form of input-regexp, output-string), disable some, etc. If anyone is interested in trying to get something here I'd be happy to provide more details. (And going back to the property, if you're looking for a way to do this for some particular value, then the right way to do this is to use the procedure property -- the text outputter treats anything that looks as a thunk by applying it to get the value to actually put out.) -- ((lambda (x) (x x)) (lambda (x) (x x))) Eli Barzilay: http://barzilay.org/ Maze is Life! Racket Users list: http://lists.racket-lang.org/users
Re: [racket] Ensuring data fed to web-server/templates is textual
On Feb 8, 2012, at 10:17 AM, Jay McCarthy wrote: web-server/templates uses scribble/text > > So, if you return a function, then it will be called. I'm not sure I understand the implication: that I could achieve what I'm after by wrapping the images in a function? I'm not clear on how that would work. > We could also change scribble/text to support a struct/class property > for JIT transformation. Does that sound good? This sounds like it might be the kind of thing I'm after. Given that I don't necessarily know how the images are being created, could attaching such a property be done without changing how the image%s are instantiated? Thanks, Jordan > Is that okay with you, Eli? > > Jay > > On Tue, Feb 7, 2012 at 4:50 PM, Jordan Johnson wrote: >> Hi all, >> >> I'm using web-server/templates to generate text, and the data in variables I >> reference in the template include s-exps that may, in some cases, contain >> image% objects. I want it to render the image%s as plain text; even just >> the string "" or similar would be adequate. >> >> So, my question is: how (via the template system or other libraries) can I >> best make racket perform this translation, ideally without writing code to >> walk the s-exp trees? It seems there must be a way someplace to tweak the >> output function used by the template library, but I don't know where that >> would be. >> >> Best, >> Jordan >> >> Racket Users list: >> http://lists.racket-lang.org/users > > > > -- > Jay McCarthy > Assistant Professor / Brigham Young University > http://faculty.cs.byu.edu/~jay > > "The glory of God is Intelligence" - D&C 93 Racket Users list: http://lists.racket-lang.org/users
Re: [racket] Ensuring data fed to web-server/templates is textual
web-server/templates uses scribble/text So, if you return a function, then it will be called. We could also change scribble/text to support a struct/class property for JIT transformation. Does that sound good? Is that okay with you, Eli? Jay On Tue, Feb 7, 2012 at 4:50 PM, Jordan Johnson wrote: > Hi all, > > I'm using web-server/templates to generate text, and the data in variables I > reference in the template include s-exps that may, in some cases, contain > image% objects. I want it to render the image%s as plain text; even just the > string "" or similar would be adequate. > > So, my question is: how (via the template system or other libraries) can I > best make racket perform this translation, ideally without writing code to > walk the s-exp trees? It seems there must be a way someplace to tweak the > output function used by the template library, but I don't know where that > would be. > > Best, > Jordan > > Racket Users list: > http://lists.racket-lang.org/users -- Jay McCarthy Assistant Professor / Brigham Young University http://faculty.cs.byu.edu/~jay "The glory of God is Intelligence" - D&C 93 Racket Users list: http://lists.racket-lang.org/users
Re: [racket] Ensuring data fed to web-server/templates is textual
Jordan Johnson wrote at 02/07/2012 06:50 PM: I'm using web-server/templates to generate text, and the data in variables I reference in the template include s-exps that may, in some cases, contain image% objects. I want it to render the image%s as plain text; even just the string "" or similar would be adequate. I don't know about "web-server/templates", but if you want to do this translation at the last minute, rather than simply avoiding putting invalid values in the s-expression in the first place, another library will do it: #lang racket/base (require (planet neil/html-writing:1:0)) (define-struct some-image-thing (x)) (define (my-html-writing-filter context thing) (cond ((some-image-thing? thing) (format "" (some-image-thing-x thing))) (else (error 'my-html-writing-filter "Don't know how to filter ~S in context ~S" thing context (write-html `(html (head (title "My Title")) (body (@ (bgcolor "white")) (h1 "My Heading") (p "This is a paragraph.") (p "This is a foreign thing: " ,(make-some-image-thing 42)) (p "This is another paragraph."))) (current-output-port) my-html-writing-filter) This writes the output: My TitleMy HeadingThis is a paragraph.This is a foreign thing:This is another paragraph. I originally implemented that feature 7 years ago, for last-minute translation of URI objects -- to output URLs as relative to the URL of the HTML object being written, rather than absolute. -- http://www.neilvandyke.org/ Racket Users list: http://lists.racket-lang.org/users
