[racket-users] On my calendar: "TR gains support for generics"

2016-09-27 Thread 'John Clements' via Racket Users
Anyone have any idea why on this date on my calendar it says, “TR gains support for generics” ? I admit, I’ve completely forgotten why I put it there…. Ah well. John -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this

Re: [racket-users] How to parse a html file into a sexpr?

2016-09-27 Thread Lin Lee
Yeah,it works. But the format is a little different to the sexpr. Thanks to your info. -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to

Re: [racket-users] TR issue with the type of expt

2016-09-27 Thread Robby Findler
Everyone knows to open a TR reply and do: > (:print-type expt) right? It's fun :) Robby On Tue, Sep 27, 2016 at 3:40 PM, Vincent St-Amour wrote: > You are correct, the implementation of `expt` is not aware of that fact. > > However, TR assigns `expt` a type

Re: [racket-users] TR issue with the type of expt

2016-09-27 Thread Vincent St-Amour
You are correct, the implementation of `expt` is not aware of that fact. However, TR assigns `expt` a type after the fact, and so is able to encode more precise properties. The particular one under discussion happens to not hold, as Pierpaolo explained. Vincent On Tue, 27 Sep 2016 08:36:43

Re: [racket-users] How to parse a html file into a sexpr?

2016-09-27 Thread Greg Trzeciak
This is more up to date version of the html-parsing package: https://pkgn.racket-lang.org/package/html-parsing On Tuesday, September 27, 2016 at 9:26:32 PM UTC+2, David K. Storrs wrote: > Yep! > > > The function is:  html->xexp and it's in (require (planet >

Re: [racket-users] How to parse a html file into a sexpr?

2016-09-27 Thread David Storrs
Yep! The function is: html->xexp and it's in (require (planet neil/html-parsing:3:0)) Note that xexp isn't *exactly* the same as sexp, but after substantial messing with it myself I can guarantee that you will find it easier. Dave On Tue, Sep 27, 2016 at 11:50 AM, Lin Lee

[racket-users] How to parse a html file into a sexpr?

2016-09-27 Thread Lin Lee
I have a problem to parse a html file into a sexpr. I plan to use the 'HTML: Parsing Library' to do this. But it's a little complicate to parse a html file. So, I just want to know if there is a lib just parse a html file into a sexpr like the example in Tutorial.2: '(html (head (title "My

Re: [racket-users] TR issue with the type of expt

2016-09-27 Thread Tim Brown
/i/ forgot about that. And there you have it: (-> Nonnegative-Real Real Real) Don’t laugh, but the irony (tragedy) is that I’m using it to implement some quaternion stuff. On 27/09/16 14:43, Pierpaolo Bernardi wrote: > On Tue, Sep 27, 2016 at 3:23 PM, Tim Brown wrote: >

Re: [racket-users] TR issue with the type of expt

2016-09-27 Thread Pierpaolo Bernardi
On Tue, Sep 27, 2016 at 3:23 PM, Tim Brown wrote: > I believe (because I can’t think of a counterexample) that > (expt Real Real) is never Complex; and therefore expt can be of type > (Real Real -> Real). What about (expt -1 1/2) ? -- You received this message because

Re: [racket-users] TR issue with the type of expt

2016-09-27 Thread Matthew Eric Bassett
I do not believe this is an oversight. The function expt has type signature (-> Number Number Number). Mathematically, yes, a^b is a real when a and b are reals. But the implementation of expt is not aware of it (it is, in principle, possible to do case-by-case types for a function, but expt

[racket-users] TR issue with the type of expt

2016-09-27 Thread Tim Brown
The following snippet: -- #lang typed/racket (: ** [Real Real -> Real]) (define (** a b) (expt a b)) -- Throws: unsaved editor:5:2: Type Checker: type mismatch expected: Real given: Number in: (expt a b) #(67 10) I believe (because I can’t

Re: [racket-users] Re: Windows and librsvg-2-2.dll

2016-09-27 Thread Jens Axel Søgaard
One thing that can go wrong (I think): If DrRacket and librsvg both depends on some library a.dll and the versions differ then interesting things can happen. As far as I know it is necessary to use the exact same version. Google tells me that librsvg depends on Pango so that's one thing to

[racket-users] Re: Windows and librsvg-2-2.dll

2016-09-27 Thread Lehi Toskin
I've long since passed the point where pulling my hair out and/or sacrificing virgin goats was the next viable step in my quest to get the libraries working, so I think I'll quit while I'm still coherent and vaguely "sane". It seems as though the bundle of DLL's that m.douglas.williams linked