<div dir="ltr"><div>Ah, so is this now why I'm getting this error?: TypeError: fr.f is not a function<br><br></div><div>Here's some screenshots of the code in the inspector: <a href="http://imgur.com/a/FBm3R">http://imgur.com/a/FBm3R</a><br></div><div><br></div><div>The code in question looks like this:<br><br>function new_map_with (init) {<br>    var acc = new Map ();<br>    var curr = init;<br>    while (curr._2 != null) {<br>        acc.set (curr._1._1, curr._1._2);<br>        curr = curr._2;}<br>    //curr._1._1 contains the last elem when curr._1._2 === null.<br>    acc.set (curr._1._1, curr._1._2);<br>    return acc;}<br></div><div><br></div>I am attempting to pass back the Map from JS back to Ur, and it seems that fr.f at runtime will hold new_map_with at first, then after it executes it then holds the Map I generates. At that point line 1991 gets called e = {c: "c", v: fr.f(v)}; and I get that error, since fr.f now holds Map {...} and Map isn't a function..<br></div><div class="gmail_extra"><br><div class="gmail_quote">On Mon, May 22, 2017 at 4:42 AM, Adam Chlipala <span dir="ltr"><<a href="mailto:adamc@csail.mit.edu" target="_blank">adamc@csail.mit.edu</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
  
    
  
  <div text="#000000" bgcolor="#FFFFFF">
    <div class="m_-170248232430822086moz-cite-prefix">I can confirm that
      non-primitive/abstract types are not meant to cross the FFI
      boundary.<div><div class="h5"><br>
      <br>
      On 05/21/2017 11:31 PM, Aistis Raulinaitis wrote:<br>
    </div></div></div><div><div class="h5">
    <blockquote type="cite">
      <div dir="ltr">Thanks!<br>
      </div>
      <div class="gmail_extra"><br>
        <div class="gmail_quote">On Sun, May 21, 2017 at 8:27 PM, Artyom
          Shalkhakov <span dir="ltr"><<a href="mailto:artyom.shalkhakov@gmail.com" target="_blank">artyom.shalkhakov@gmail.com</a>></span>
          wrote:<br>
          <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><span>2017-05-22 9:19 GMT+06:00 Aistis Raulinaitis <<a href="mailto:sheganinans@gmail.com" target="_blank">sheganinans@gmail.com</a>>:<br>
              > Hmm, that makes sense. Do you have an example of FFI
              with an abstract type?<br>
              > I tried to encapsulate the map type with a con, but
              obviously that does not<br>
              > work..<br>
              ><br>
              <br>
            </span>Sure, here are two examples:<br>
            <br>
            <a href="https://github.com/bbarenblat/urweb-regex" rel="noreferrer" target="_blank">https://github.com/bbarenblat/<wbr>urweb-regex</a>
            (in particular, take a look<br>
            at regex__FFI.urs and the two types [substring_t] and<br>
            [substring_list_t])<br>
            <a href="https://github.com/ashalkhakov/urweb-storage" rel="noreferrer" target="_blank">https://github.com/ashalkhakov<wbr>/urweb-storage</a>
            (shameless plug; in<br>
            particular, take a look at storage__FFI.urs and the type
            [storage])<br>
            <div class="m_-170248232430822086HOEnZb">
              <div class="m_-170248232430822086h5"><br>
                > On Sun, May 21, 2017 at 8:10 PM, Artyom Shalkhakov<br>
                > <<a href="mailto:artyom.shalkhakov@gmail.com" target="_blank">artyom.shalkhakov@gmail.com</a>>
                wrote:<br>
                >><br>
                >> 2017-05-22 6:22 GMT+06:00 Aistis Raulinaitis
                <<a href="mailto:sheganinans@gmail.com" target="_blank">sheganinans@gmail.com</a>>:<br>
                >> > So I am working with the JS FFI, however
                it seems that the clientOnly<br>
                >> > directive is being ignored.<br>
                >> ><br>
                >> > Here is the example code:<br>
                >> ><br>
                >> > ~~~<br>
                >> > main.urp:<br>
                >> > ~~~<br>
                >> ><br>
                >> > ffi js_map<br>
                >> > jsFunc Js_map.new_map=new_map<br>
                >> > jsFunc Js_map.new_map_with=new_map_wi<wbr>th<br>
                >> > clientOnly Js_map.new_map<br>
                >> > clientOnly Js_map.new_map_with<br>
                >> > benignEffectful Js_map.new_map<br>
                >> > benignEffectful Js_map.new_map_with<br>
                >> > jsFile js_map.js<br>
                >> ><br>
                >> > main<br>
                >> ><br>
                >> ><br>
                >> > ~~~<br>
                >> > main.urs:<br>
                >> > ~~~<br>
                >> ><br>
                >> > val main : unit -> transaction page<br>
                >> ><br>
                >> ><br>
                >> > ~~~<br>
                >> > main.ur:<br>
                >> > ~~~<br>
                >> ><br>
                >> > fun main () =<br>
                >> >     c <- Js_map.new_map_with ((1,
                2)::[]);<br>
                >> >     return <xml></xml><br>
                >> ><br>
                >> ><br>
                >> > ~~~<br>
                >> > js_map.urs:<br>
                >> > ~~~<br>
                >> ><br>
                >> > con js_map :: Type -> Type -> Type<br>
                >> ><br>
                >> > val new_map      : k ::: Type -> v :::
                Type -> unit -> transaction<br>
                >> > (js_map k<br>
                >> > v)<br>
                >> > val new_map_with : k ::: Type -> v :::
                Type -> list (k * v) -><br>
                >> > transaction<br>
                >> > (js_map k v)<br>
                >> ><br>
                >> ><br>
                >> > ~~~<br>
                >> > js_map.js:<br>
                >> > ~~~<br>
                >> ><br>
                >> > function new_map () {return new Map ();}<br>
                >> ><br>
                >> > function new_map_with (arg) {return new
                Map (arg); }<br>
                >> ><br>
                >> ><br>
                >> > ~~~<br>
                >> > So in main.ur, you can see that I am
                calling this Js code in a C<br>
                >> > context,<br>
                >> > instead of getting an error complaining
                about how it should be called on<br>
                >> > the<br>
                >> > client, instead I get this confusing
                error:<br>
                >> ><br>
                >> > urweb main<br>
                >> > /Users/ace/src/cli_only/js_map<wbr>.urs:4:75:
                (to 4:87) Unsupported type<br>
                >> > constructor<br>
                >> > Constructor:  FFI(Js_map.js_map_with)
                FFI(Basis.int) FFI(Basis.int)<br>
                >> > /usr/local/Cellar/urweb/201701<wbr>05/lib/urweb/ur/basis.urs:127:<wbr>23:
                (to<br>
                >> > 127:25)<br>
                >> > Unsupported type constructor<br>
                >> > Constructor:  FFI(Js_map.js_map_with)
                FFI(Basis.int) FFI(Basis.int)<br>
                >> > make: *** [all] Error 1<br>
                >> ><br>
                >><br>
                >> I got the impression that Ur/Web being a
                whole-program optimizing<br>
                >> compiler, the only types being supported for
                marshalling between FFI<br>
                >> code and non-FFI code are primitive types and
                abstract types. I think<br>
                >> I asked this same question some time ago.<br>
                >><br>
                >> So it looks like you will have to work around
                this somehow.<br>
                >><br>
                >> ><br>
                >> ><br>
                >> > ______________________________<wbr>_________________<br>
                >> > Ur mailing list<br>
                >> > <a href="mailto:Ur@impredicative.com" target="_blank">Ur@impredicative.com</a><br>
                >> > <a href="http://www.impredicative.com/cgi-bin/mailman/listinfo/ur" rel="noreferrer" target="_blank">http://www.impredicative.com/c<wbr>gi-bin/mailman/listinfo/ur</a><br>
                >> ><br>
                >><br>
                >><br>
                >><br>
                >> --<br>
                >> Cheers,<br>
                >> Artyom Shalkhakov<br>
                >><br>
                >> ______________________________<wbr>_________________<br>
                >> Ur mailing list<br>
                >> <a href="mailto:Ur@impredicative.com" target="_blank">Ur@impredicative.com</a><br>
                >> <a href="http://www.impredicative.com/cgi-bin/mailman/listinfo/ur" rel="noreferrer" target="_blank">http://www.impredicative.com/c<wbr>gi-bin/mailman/listinfo/ur</a><br>
                ><br>
                ><br>
                ><br>
                > ______________________________<wbr>_________________<br>
                > Ur mailing list<br>
                > <a href="mailto:Ur@impredicative.com" target="_blank">Ur@impredicative.com</a><br>
                > <a href="http://www.impredicative.com/cgi-bin/mailman/listinfo/ur" rel="noreferrer" target="_blank">http://www.impredicative.com/c<wbr>gi-bin/mailman/listinfo/ur</a><br>
                ><br>
                <br>
                <br>
                <br>
                --<br>
                Cheers,<br>
                Artyom Shalkhakov<br>
                <br>
                ______________________________<wbr>_________________<br>
                Ur mailing list<br>
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              </div>
            </div>
          </blockquote>
        </div>
        <br>
      </div>
      <br>
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      <br>
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    </blockquote>
    <p><br>
    </p>
  </div></div></div>

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