[Twisted-web] Nevow: directive("header")

[Mary Gardiner]

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Hi,

I've been learned Nevow mainly by instinct, so this may be documented
somewhere and I can't find it.

If I wanted to produce XML that looks something like:

<tag1>
    <tag2/>
    <tag3/>
    <tag4/>
    <tag4/>
    ...
    <tag4/>
</tag1>

how would I do it?

I am using render = directive("sequence") for tag1, and pattern = "item"
for tag4.

This works fine for:

<tag1>
    <tag4/>
    <tag4/>
    ...
    <tag4/>
</tag1>

but I want to include those extra tags. I thought setting render =
directive("heading") on tag2 and tag3 might work, but it gives the
following error:

    File "/home/mary/src/Nevow/nevow/accessors.py", line 53, in child
        return self.original[int(name)]
    exceptions.ValueError: invalid literal for int(): header

after a long traceback.

The two attached files should demonstrate the problem: noheader.py
works, header.py gives the error mentioned.

Is this a bug or am I simply going about this the wrong way?

-Mary

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from nevow import rend, stan, tags, appserver
from twisted.application import service, internet

class TestHeader(rend.Page):

    def data_list(self, context, data):
        return ["item 1", "item 2", "item 3"]

    def data_header(self, context, data):
        return "header"

    def render_plain(self, context, data):
        return context.tag[data]

    docFactory = rend.stan(tags.html[
        tags.body(render = stan.directive("sequence"), data = stan.directive("list"))[
            tags.p(pattern = "item", render = stan.directive("plain"))
        ]
    ])

application = service.Application("Header pattern test")
internet.TCPServer(
    8080,
    appserver.NevowSite(
        TestHeader()
    )
).setServiceParent(application)

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from nevow import rend, stan, tags, appserver
from twisted.application import service, internet

class TestHeader(rend.Page):

    def data_list(self, context, data):
        return ["item 1", "item 2", "item 3"]

    def data_header(self, context, data):
        return "header"

    def render_plain(self, context, data):
        return context.tag[data]

    docFactory = rend.stan(tags.html[
        tags.body(render = stan.directive("sequence"), data = stan.directive("list"))[
            tags.h1(data = stan.directive("header"), pattern = "header"),
            tags.p(pattern = "item", render = stan.directive("plain"))
        ]
    ])

application = service.Application("Header pattern test")
internet.TCPServer(
    8080,
    appserver.NevowSite(
        TestHeader()
    )
).setServiceParent(application)

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