OMG
So, as -> begins with "-" then it has the precedence of the operator
-????
On Sep 8, 7:52 pm, Naftoli Gugenheim <naftoli...@gmail.com> wrote:
> Precedence is determined by the first character of an operator.
>
> -------------------------------------
>
> Ross Mellgren<dri...@gmail.com> wrote:
>
> Because the compiler interpret your expression as you expect. Instead
> of:
>
> "url_enlace" -> ("/product/" + product.id.toString)
>
> which is what you wanted, it got:
>
> ("url_enlace" -> "/product/") + product.id.toString)
>
> which it can do because it can take an arbitrary object:
>
> ("url_enlace" -> "/product/"): ABindParam
> or (the other implicit ->)
> ("url_enlace" -> "/product/"): Tuple2[String, String]
>
> and convert them to strings. Of course, once it converts to string, it
> won't fit in bind()'s argument list and so it gave you the could not
> find overload error.
>
> Honestly I'm a bit fuzzy on Scala's operator precedence behavior, I
> think if I recall you can't set precedence, it comes pre-set on all
> the standard operators like + / -, etc.
>
> -Ross
>
> On Sep 8, 2009, at 3:42 PM, José María wrote:
>
>
>
> > It worked when I put the () around the bind param!!!!
>
> > and the question is ... why?
>
> > On Sep 8, 7:35 pm, Ross Mellgren <dri...@gmail.com> wrote:
> >> So that doesn't seem to be a box-related thing so much as a bind
> >> argument related thing, probably because you have a precedence
> >> problem... try:
>
> >> producto.map(product =>
> >> bind("product", xhtml,
> >> "url_enlace" -> ("/product/" + product.id.toString),
> >> )
> >> ).openOr(NodeSeq.Empty)
>
> >> Also, FYI, you have val product = Product.find(id), but then map over
> >> producto. I presume either producto is coming from somewhere else
> >> (and
> >> val product is being shadowed inside the map) or that you pasted not
> >> exactly what you're compiling.
>
> >> -Ross
>
> >> On Sep 8, 2009, at 3:25 PM, José María wrote:
>
> >>> That's my code:
>
> >>> val product = Product.find(id)
>
> >>> producto.map(product =>
> >>> bind("product", xhtml,
> >>> "url_enlace" --> "/product/" + product.id.toString ,
> >>> )
> >>> ).openOr(NodeSeq.Empty)
> >>> }
>
> >>> and I get this error:
>
> >>> [INFO] use java command with args in file forced : false
> >>> /usr/home/josemaria/src/lift/helloworld/src/main/scala/demo/
> >>> helloworld/
> >>> snippet/Portada.scala:55: error: overloaded method value bind with
> >>> alternatives (String,net.liftweb.util.Box[(scala.xml.NodeSeq) =>
> >>> scala.xml.NodeSeq],net.liftweb.util.Box
> >>> [(scala.xml.PrefixedAttribute)
> >>> =>
> >>> scala.xml.MetaData
> >>> ],scala.xml.NodeSeq,net.liftweb.util.Helpers.BindParam*)
> >>> scala.xml.NodeSeq <and>
> >>> (String,scala.xml.NodeSeq,net.liftweb.util.Helpers.BindParam*)
> >>> scala.xml.NodeSeq cannot be applied to
> >>> (java.lang.String
> >>> ,scala.xml.NodeSeq
> >>> ,java.lang.String
> >>> ,java.lang.String
> >>> ,net.liftweb.util.Helpers.BindParam
> >>> ,net.liftweb.util.Helpers.BindParam)
> >>> bind("producto", xhtml,
> >>> ^
> >>> one error found
>
> >>> What's wrong?
>
> >>> On Sep 8, 7:13 pm, Ross Mellgren <dri...@gmail.com> wrote:
> >>>> Well it depends on precisely what you want. If you want your
> >>>> snippet
> >>>> to become empty if the product is not there, try:
>
> >>>> productBox.map(product => {
> >>>> bind("product", ns, ...)
>
> >>>> }).openOr(NodeSeq.Empty)
>
> >>>> If you want only certain bind positions empty, do the same thing
> >>>> inside the bind:
>
> >>>> bind("proudct", ns,
> >>>> "field" -> productBox.map(p => Text(p.field.toString)).openOr
> >>>> (NodeSeq.Empty),
> >>>> ...)
>
> >>>> map is of course just one of the (simpler) operations you can do
> >>>> with
> >>>> a Box, there's more complicated stuff if you need other variants.
>
> >>>> -Ross
>
> >>>> On Sep 8, 2009, at 3:06 PM, José María wrote:
>
> >>>>> Hi.
>
> >>>>> Boxes are giving me a hard time.
>
> >>>>> Say you have a model of a Product.
>
> >>>>> If I've a snippet that retrieves a Product from the DB:
>
> >>>>> val product : Box[Product] = Product.find(2)
>
> >>>>> And now I want to bind "product" with bind(), product is a Box
> >>>>> and it
> >>>>> can be empty, how can I bind something that doesn't exists? You
> >>>>> have
> >>>>> to return a NodeSeq in a snippet. What should my code must do?
>
> >>>>> Best regards.
>
>
--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups
"Lift" group.
To post to this group, send email to liftweb@googlegroups.com
To unsubscribe from this group, send email to
liftweb+unsubscr...@googlegroups.com
For more options, visit this group at
http://groups.google.com/group/liftweb?hl=en
-~----------~----~----~----~------~----~------~--~---
