Jonas Mellin
2018-04-16 08:58:15 UTC
Dear all, I am a novice with respect to UR/Web and I want to use it together with SVG. I found the prototype ffi for SVG at https://github.com/karsar/urweb-examples/tree/master/SVGTest
after reading through the material, doing all the tutorials and generally digging around internet.
Anyway, I took the example from https://github.com/karsar/urweb-examples/tree/master/SVGTest
and tried to modify it; I fail repeatedly, so now I turn to this email list.
Instead of the SVGTest.ur that has all the functionality in main, I tried to break it out to a separate function "proc". I took the idea from http://www.impredicative.com/ur/demo/sql.html
to generate an html page into a variable and then add that as return statement in the main function as seen below.
===== Modified SVGTest.ur with respect to https://github.com/karsar/urweb-examples/tree/master/SVGTest
open SVG
con intPair = int*int
fun fst (x: intPair) = x.1
fun snd (x: intPair) = x.2
fun circleDraw(x: intPair): xsvg =
<xml>
<circle cx={show ((fst x)-60)} cy={show ((snd x)-100)} r="10" stroke="red" fill="blue"/>
</xml>
fun proc (x: intPair) =
x <- source x;
return
<xml>
<body onmousemove={fn ev => set x (ev.ScreenX,ev.SceenY)}>
<div style="width:800; heigth:800">
<dyn signal={x<-signal x;
return
<xml>
<svg width="800" height="800">
{circleDraw x}
</svg>
</xml>}/>
</div>
</body>
</xml>
fun main(): transaction page =
xml <- proc (0,0);
return
<xml>
<head>
Banzai
</head>
<body>
{xml}
</body>
</xml>
I have tried different options (e.g., that the proc should return transaction page, xbody, xsvg) and I fail in different ways. (I tried to add other functionality initially, but I removed it to try to get to the bottom of the problem).
The compiler tells me:
urweb SVGTest
/home/a/SVGTest2/SVGTest.ur:33:4: (to 44:2) Error in final record unification
Can't unify record constructors
Have: [Dyn = (), MakeForm = (), Body = ()]
Need: [Html = ()]
/home/a/SVGTest2/SVGTest.ur:33:4: (to 44:2) Stuck unifying these records after canceling matching pieces:
Have: [Dyn = (), MakeForm = (), Body = ()]
Need: [Html = ()]
/home/a/SVGTest2/SVGTest.ur:17:7: (to 17:64) Error in final record unification
Can't unify record constructors
Have:
[Data = data_attr, Onload = transaction {},
Onresize = transaction {}, Onunload = transaction {},
Onhashchange = transaction {},
[<<< REMOVED to reduce size of message>>>]
Value 1:
{ScreenX : int, ScreenY : int, ClientX : int, ClientY : int,
CtrlKey : bool, ShiftKey : bool, AltKey : bool, MetaKey : bool,
Button : mouseButton} -> transaction {}
Value 2:
$(([ScreenX = int, SceenY = int]) ++ <UNIF:U141::{Type}>) ->
transaction {}
Can't unify record constructors
Have:
[ScreenX = int, ScreenY = int, ClientX = int, ClientY = int,
CtrlKey = bool, ShiftKey = bool, AltKey = bool, MetaKey = bool,
Button = mouseButton]
Need: <UNIF:U141::{Type}> ++ [ScreenX = int, SceenY = int]
Compilation exited abnormally with code 1 at Wed Apr 11 08:45:06
Thanks in advance, Jonas Mellin, Senior Lecturer, University of Skövde
after reading through the material, doing all the tutorials and generally digging around internet.
Anyway, I took the example from https://github.com/karsar/urweb-examples/tree/master/SVGTest
and tried to modify it; I fail repeatedly, so now I turn to this email list.
Instead of the SVGTest.ur that has all the functionality in main, I tried to break it out to a separate function "proc". I took the idea from http://www.impredicative.com/ur/demo/sql.html
to generate an html page into a variable and then add that as return statement in the main function as seen below.
===== Modified SVGTest.ur with respect to https://github.com/karsar/urweb-examples/tree/master/SVGTest
open SVG
con intPair = int*int
fun fst (x: intPair) = x.1
fun snd (x: intPair) = x.2
fun circleDraw(x: intPair): xsvg =
<xml>
<circle cx={show ((fst x)-60)} cy={show ((snd x)-100)} r="10" stroke="red" fill="blue"/>
</xml>
fun proc (x: intPair) =
x <- source x;
return
<xml>
<body onmousemove={fn ev => set x (ev.ScreenX,ev.SceenY)}>
<div style="width:800; heigth:800">
<dyn signal={x<-signal x;
return
<xml>
<svg width="800" height="800">
{circleDraw x}
</svg>
</xml>}/>
</div>
</body>
</xml>
fun main(): transaction page =
xml <- proc (0,0);
return
<xml>
<head>
Banzai
</head>
<body>
{xml}
</body>
</xml>
I have tried different options (e.g., that the proc should return transaction page, xbody, xsvg) and I fail in different ways. (I tried to add other functionality initially, but I removed it to try to get to the bottom of the problem).
The compiler tells me:
urweb SVGTest
/home/a/SVGTest2/SVGTest.ur:33:4: (to 44:2) Error in final record unification
Can't unify record constructors
Have: [Dyn = (), MakeForm = (), Body = ()]
Need: [Html = ()]
/home/a/SVGTest2/SVGTest.ur:33:4: (to 44:2) Stuck unifying these records after canceling matching pieces:
Have: [Dyn = (), MakeForm = (), Body = ()]
Need: [Html = ()]
/home/a/SVGTest2/SVGTest.ur:17:7: (to 17:64) Error in final record unification
Can't unify record constructors
Have:
[Data = data_attr, Onload = transaction {},
Onresize = transaction {}, Onunload = transaction {},
Onhashchange = transaction {},
[<<< REMOVED to reduce size of message>>>]
Value 1:
{ScreenX : int, ScreenY : int, ClientX : int, ClientY : int,
CtrlKey : bool, ShiftKey : bool, AltKey : bool, MetaKey : bool,
Button : mouseButton} -> transaction {}
Value 2:
$(([ScreenX = int, SceenY = int]) ++ <UNIF:U141::{Type}>) ->
transaction {}
Can't unify record constructors
Have:
[ScreenX = int, ScreenY = int, ClientX = int, ClientY = int,
CtrlKey = bool, ShiftKey = bool, AltKey = bool, MetaKey = bool,
Button = mouseButton]
Need: <UNIF:U141::{Type}> ++ [ScreenX = int, SceenY = int]
Compilation exited abnormally with code 1 at Wed Apr 11 08:45:06
Thanks in advance, Jonas Mellin, Senior Lecturer, University of Skövde