[Lift] Re: Template help
On Wed, Nov 11, 2009 at 12:35 AM, aw anth...@whitford.com wrote: I need to create a snippet sequence that looks something like this: a href=next span class=namename/span span class=commentdescription/span span class=arrow/ /a The anchor needs to be generated using SHtml.link, and name description need to be bound. As a result, I end up with a template sequence like this: b1:link span class=nameb2:name//span span class=commentb2:description//span span class=arrow/ /b1:link Then, I need snippet code that does something like: bind(b1, xhtml, link - SHtml.link(S.contextPath, () = clicked(b), bind(b2, chooseTemplate(b1, link, xhtml), name - Text(b.name), description - Text(b.description) )) Why are you using S.contextPath? But: bind(b1, xhtml, link - kids = SHtml.link(/, () = clicked(b), bind(b2, kids, name - b.name.is, description - b.description.is ))) Yuk... I'm just not happy with this. Sure, I could make it a little more readable, but this still seems unnecessarily complex and verbose. I also really don't like how the view logic is dictating my binding logic. In other words, if I wanted to change my view organization, there is a high chance that I also need to change my binding logic -- and that just isn't right... Is there a better strategy? -- Lift, the simply functional web framework http://liftweb.net Beginning Scala http://www.apress.com/book/view/1430219890 Follow me: http://twitter.com/dpp Surf the harmonics --~--~-~--~~~---~--~~ 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 -~--~~~~--~~--~--~---
[Lift] Re: Template help
You might need to surround the kids = ... function with parenthesis. - David Pollakfeeder.of.the.be...@gmail.com wrote: On Wed, Nov 11, 2009 at 12:35 AM, aw anth...@whitford.com wrote: I need to create a snippet sequence that looks something like this: a href=next span class=namename/span span class=commentdescription/span span class=arrow/ /a The anchor needs to be generated using SHtml.link, and name description need to be bound. As a result, I end up with a template sequence like this: b1:link span class=nameb2:name//span span class=commentb2:description//span span class=arrow/ /b1:link Then, I need snippet code that does something like: bind(b1, xhtml, link - SHtml.link(S.contextPath, () = clicked(b), bind(b2, chooseTemplate(b1, link, xhtml), name - Text(b.name), description - Text(b.description) )) Why are you using S.contextPath? But: bind(b1, xhtml, link - kids = SHtml.link(/, () = clicked(b), bind(b2, kids, name - b.name.is, description - b.description.is ))) Yuk... I'm just not happy with this. Sure, I could make it a little more readable, but this still seems unnecessarily complex and verbose. I also really don't like how the view logic is dictating my binding logic. In other words, if I wanted to change my view organization, there is a high chance that I also need to change my binding logic -- and that just isn't right... Is there a better strategy? -- Lift, the simply functional web framework http://liftweb.net Beginning Scala http://www.apress.com/book/view/1430219890 Follow me: http://twitter.com/dpp Surf the harmonics --~--~-~--~~~---~--~~ 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 -~--~~~~--~~--~--~---
[Lift] Re: Template help
OK, your suggestion definitely makes the snippet code more readable, but I fear I didn't make my point clear because the snippet code still is highly coupled with the view layout. Imagine that I want to change my view from this: a href=next span class=namename/span span class=commentdescription/span span class=arrow/ /a to this: span class=namename/span span class=commentdescription/span a href=next span class=arrow/ /a This would mean that I need to change my template from: b1:link span class=nameb2:name//span span class=commentb2:description//span span class=arrow/ /b1:link to this: span class=nameb:name//span span class=commentb:description//span b:link span class=arrow/ /b:link And then I need to update my code from: bind(b1, xhtml, link - kids = SHtml.link(next, () = clicked(b), bind(b2, kids, name - b.name.is, description - b.description.is ))) to something like this: bind(b, xhtml, name - b.name.is, description - b.description.is, link - kids = SHtml.link(next, () = clicked(b)) ))) My complaint is that reorganizing the view is tending to require code changes at the snippet level. And that just doesn't seem right to me. At first, I thought that I could leverage the recursive nature of snippets. In other words, I thought I could avoid the b1 and b2 binding keys and simply use b, then when the first round contained more b variables to bind, it would recurse. Alas, this didn't work (I'm sorry, but I don't recall the error message). But this was what I was thinking: b:link span class=nameb:name//span span class=commentb:description//span span class=arrow/ /b:link or this: span class=nameb:name//span span class=commentb:description//span b:link span class=arrow/ /b:link and the code would remain this: bind(b, xhtml, name - b.name.is, description - b.description.is, link - kids = SHtml.link(next, () = clicked(b)) ))) --~--~-~--~~~---~--~~ 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 -~--~~~~--~~--~--~---
[Lift] Re: Template help
You can do a recursive bind, but you must make it explicit:
def mySnippet(xhtml: NodeSeq): NodeSeq = {
def doBind(xhtml: NodeSeq): NodeSeq =
bind(b, xhtml,
link - { (kids: NodeSeq) = SHtml.link(next, () =
clicked(b), doBind(kids)) },
name - the name,
description - the description)
doBind(xhtml)
}
-Ross
On Nov 11, 2009, at 1:21 PM, aw wrote:
OK, your suggestion definitely makes the snippet code more readable,
but I fear I didn't make my point clear because the snippet code still
is highly coupled with the view layout.
Imagine that I want to change my view from this:
a href=next
span class=namename/span
span class=commentdescription/span
span class=arrow/
/a
to this:
span class=namename/span
span class=commentdescription/span
a href=next
span class=arrow/
/a
This would mean that I need to change my template from:
b1:link
span class=nameb2:name//span
span class=commentb2:description//span
span class=arrow/
/b1:link
to this:
span class=nameb:name//span
span class=commentb:description//span
b:link
span class=arrow/
/b:link
And then I need to update my code from:
bind(b1, xhtml,
link - kids = SHtml.link(next, () = clicked(b),
bind(b2, kids, name - b.name.is, description -
b.description.is
)))
to something like this:
bind(b, xhtml,
name - b.name.is,
description - b.description.is,
link - kids = SHtml.link(next, () = clicked(b))
)))
My complaint is that reorganizing the view is tending to require code
changes at the snippet level. And that just doesn't seem right to me.
At first, I thought that I could leverage the recursive nature of
snippets. In other words, I thought I could avoid the b1 and b2
binding keys and simply use b, then when the first round contained
more b variables to bind, it would recurse. Alas, this didn't work
(I'm sorry, but I don't recall the error message). But this was what
I was thinking:
b:link
span class=nameb:name//span
span class=commentb:description//span
span class=arrow/
/b:link
or this:
span class=nameb:name//span
span class=commentb:description//span
b:link
span class=arrow/
/b:link
and the code would remain this:
bind(b, xhtml,
name - b.name.is,
description - b.description.is,
link - kids = SHtml.link(next, () = clicked(b))
)))
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[Lift] Re: Template help
On Wed, Nov 11, 2009 at 11:21 AM, aw anth...@whitford.com wrote: OK, your suggestion definitely makes the snippet code more readable, but I fear I didn't make my point clear because the snippet code still is highly coupled with the view layout. If this was a MVC type framework, I think you're point would be valid. But it isn't a MVC framework. The snippet is tightly coupled to the xhtml, because it's the dynamic part of the xhtml. The best way to mitigate these kinds of changes is to design the UI first, then build the snippets. That way, you're not rearranging as often. See this article for a better understanding: http://wiki.liftweb.net/index.php?title=Lift_View_First Imagine that I want to change my view from this: a href=next span class=namename/span span class=commentdescription/span span class=arrow/ /a to this: span class=namename/span span class=commentdescription/span a href=next span class=arrow/ /a This would mean that I need to change my template from: b1:link span class=nameb2:name//span span class=commentb2:description//span span class=arrow/ /b1:link to this: span class=nameb:name//span span class=commentb:description//span b:link span class=arrow/ /b:link And then I need to update my code from: bind(b1, xhtml, link - kids = SHtml.link(next, () = clicked(b), bind(b2, kids, name - b.name.is, description - b.description.is ))) to something like this: bind(b, xhtml, name - b.name.is, description - b.description.is, link - kids = SHtml.link(next, () = clicked(b)) ))) My complaint is that reorganizing the view is tending to require code changes at the snippet level. And that just doesn't seem right to me. At first, I thought that I could leverage the recursive nature of snippets. In other words, I thought I could avoid the b1 and b2 binding keys and simply use b, then when the first round contained more b variables to bind, it would recurse. Alas, this didn't work (I'm sorry, but I don't recall the error message). But this was what I was thinking: b:link span class=nameb:name//span span class=commentb:description//span span class=arrow/ /b:link or this: span class=nameb:name//span span class=commentb:description//span b:link span class=arrow/ /b:link and the code would remain this: bind(b, xhtml, name - b.name.is, description - b.description.is, link - kids = SHtml.link(next, () = clicked(b)) ))) -- James A Barrows --~--~-~--~~~---~--~~ 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 -~--~~~~--~~--~--~---
[Lift] Re: Template help
I didn't see Tim's blog post, but another option is to bind in two passes. First bind the outer level: b1:link should become an SHtml.link, preserving the same set of child elements. So here use a NodeSeq function: kids = SHtml.link(..., kids). Then pass the resulting NodeSeq to a bind invocation that transforms your other elements. You can place this in one statement, by using one call to bind as the NodeSeq argument to the other call. And you can use the implicit in BindPlus to chain bind calls: xhtml.bind(prefix, bindParams ... ).bind(pre2, ...) That said, I think there is a fundamental, inevitable tension between separation of view and logic, and repetition (not really your point). I tried to address this, as it applies to Mapper fields, to a small extent in ModelView. However if anyone has better ideas of how to do things I'm very interested to hear! - Timothy Perretttimo...@getintheloop.eu wrote: Take a look at: http://logji.blogspot.com/2009/09/composable-bindings-in-lift.html and then: http://logji.blogspot.com/2009/10/composable-bindings-in-lift-part-ii.html Sounds like this could provide a more flexible implementation pattern for your use case. Cheers, Tim On 11 Nov 2009, at 18:21, aw wrote: OK, your suggestion definitely makes the snippet code more readable, but I fear I didn't make my point clear because the snippet code still is highly coupled with the view layout. Imagine that I want to change my view from this: a href=next span class=namename/span span class=commentdescription/span span class=arrow/ /a to this: span class=namename/span span class=commentdescription/span a href=next span class=arrow/ /a This would mean that I need to change my template from: b1:link span class=nameb2:name//span span class=commentb2:description//span span class=arrow/ /b1:link to this: span class=nameb:name//span span class=commentb:description//span b:link span class=arrow/ /b:link And then I need to update my code from: bind(b1, xhtml, link - kids = SHtml.link(next, () = clicked(b), bind(b2, kids, name - b.name.is, description - b.description.is ))) to something like this: bind(b, xhtml, name - b.name.is, description - b.description.is, link - kids = SHtml.link(next, () = clicked(b)) ))) My complaint is that reorganizing the view is tending to require code changes at the snippet level. And that just doesn't seem right to me. At first, I thought that I could leverage the recursive nature of snippets. In other words, I thought I could avoid the b1 and b2 binding keys and simply use b, then when the first round contained more b variables to bind, it would recurse. Alas, this didn't work (I'm sorry, but I don't recall the error message). But this was what I was thinking: b:link span class=nameb:name//span span class=commentb:description//span span class=arrow/ /b:link or this: span class=nameb:name//span span class=commentb:description//span b:link span class=arrow/ /b:link and the code would remain this: bind(b, xhtml, name - b.name.is, description - b.description.is, link - kids = SHtml.link(next, () = clicked(b)) ))) --~--~-~--~~~---~--~~ 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 -~--~~~~--~~--~--~---
