StatefulSnippets lifetime is manually managed and may be "chained" to other pages by using link() or redirectTo() such that the same instance is reused for those targets.
(And StatefulSnippet extends DispatchSnippet) alex On Mon, Dec 28, 2009 at 10:08 AM, Naftoli Gugenheim <naftoli...@gmail.com>wrote: > And what's the difference to a StatefulSnippet? > > ------------------------------------- > Adam Warski<a...@warski.org> wrote: > > Hello, > > > RequestVar-s lifetime is expanded beyond the actual request, which is > > not applicable for TransientRequestVar. For instance say you have a > > page and you set some state on a RequestVar ... then you render an > > Ajax link. After the page is rendered, when your ajax function is > > invoked, you RequestVar state set when rendering the page is still > > visible. > > > > But is there is problem you're chasing or is it just terminology? > I understand the difference; and I think the terminology is a bit > misleading. But right now I have two questions: > > 1) Can I have in lift a "true" request variable/snippet, that is such which > has a lifetime of one request (without any ajax callbacks)? I can't use > TransientRequestVar because it's private. It would be useful to complete my > ajax-form example (after an item is saved, a new one should be used; I guess > I could just store the model instance in a RequestVar and set it to a new > object after saving, but maybe there's a nicer way). > > 2) Why would one want to use DispatchSnippets? The wiki says they are > better because they are not instantiated whenever a tag is occurred. But > right now, reflection snippets also aren't - they are instantiated at most > once per request. > > > Br's, > > Marius > > > > On Dec 28, 6:04 pm, Adam Warski <a...@warski.org> wrote: > >> Hello, > >> > >>> Yes, the article is out of date now... Lift now makes sure that > multiple references to a single snippet in the same request context use the > same instance of that snippet. > >> > >> I see, so the rationale behind using dispatch snippets is out of date > also. Except that you save one reflection call per page/request. So are > there any reasons to use DispatchSnippets now? > >> > >>> Reflection snippets do not have the same scope as request vars... > rather, the snippet is held in a request var. > >> > >> Which essentialy makes them have the same scope as request vars :) > >> > >> By the way, is there a "true" request-scope variable? I saw that there's > TransientRequestVar, but it's private in the liftweb package. > >> > >> Adam > >> > >>> Cheers, Tim > >> > >>> On 28 Dec 2009, at 14:33, Adam Warski wrote: > >> > >>>> Hello, > >> > >>>> on the wiki page about reflection snippets ( > http://wiki.github.com/dpp/liftweb/about-snippets), it is written: > >> > >>>> "Every time you call the reflection snippet in your markup code, a new > instance is instantiated and the appropriate method invoked" > >> > >>>> However this doesn't seem to be true (I'm using 1.1-M8). I have > modified the example in the tutorial to use ajax to submit the form (as > Marius and others advised me in another thread), and I discovered that after > I add an item, then try to add another one, the first one is modified, which > would mean that the same snippet instance is used (the snippet - TD - is a > reflection snippet, as far as I understand the terminology). > >> > >>>> That would mean that reflection snippets have the same scope as > RequestVars, that is that there's at most one instance per rendered page. > Marius wrote that this changes recently, so maybe it's a side-effect? > >> > >>>> Also, do you think that "RequestVar" is a good name? For me it > suggests a variable which has a lifecycle only for one http request. In the > Seam framework, for example, there are two scopes: request and page (and > many others), the first one being a "true" request scope, the second having > essentially the same scope as RequestVar. So maybe it should be called > PageVar? > >> > >>>> -- > >>>> Adam > >> > >>>> -- > >> > >>>> You received this message because you are subscribed to the Google > Groups "Lift" group. > >>>> To post to this group, send email to lift...@googlegroups.com. > >>>> To unsubscribe from this group, send email to > liftweb+unsubscr...@googlegroups.com<liftweb%2bunsubscr...@googlegroups.com> > . > >>>> For more options, visit this group athttp:// > groups.google.com/group/liftweb?hl=en. > >> > >>> -- > >> > >>> You received this message because you are subscribed to the Google > Groups "Lift" group. > >>> To post to this group, send email to lift...@googlegroups.com. > >>> To unsubscribe from this group, send email to > liftweb+unsubscr...@googlegroups.com<liftweb%2bunsubscr...@googlegroups.com> > . > >>> For more options, visit this group athttp:// > groups.google.com/group/liftweb?hl=en. > > > > -- > > > > You received this message because you are subscribed to the Google Groups > "Lift" group. > > To post to this group, send email to lift...@googlegroups.com. > > To unsubscribe from this group, send email to > liftweb+unsubscr...@googlegroups.com<liftweb%2bunsubscr...@googlegroups.com> > . > > For more options, visit this group at > http://groups.google.com/group/liftweb?hl=en. > > > > > > -- > > You received this message because you are subscribed to the Google Groups > "Lift" group. > To post to this group, send email to lift...@googlegroups.com. > To unsubscribe from this group, send email to > liftweb+unsubscr...@googlegroups.com<liftweb%2bunsubscr...@googlegroups.com> > . > For more options, visit this group at > http://groups.google.com/group/liftweb?hl=en. > > > -- > > You received this message because you are subscribed to the Google Groups > "Lift" group. > To post to this group, send email to lift...@googlegroups.com. > To unsubscribe from this group, send email to > liftweb+unsubscr...@googlegroups.com<liftweb%2bunsubscr...@googlegroups.com> > . > For more options, visit this group at > http://groups.google.com/group/liftweb?hl=en. > > > -- You received this message because you are subscribed to the Google Groups "Lift" group. 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