%eyre stack trace from using +-urn:by wrong.

This generator:

/?  310
::
!:
::
:-  %say  |=  *
:-  %noun
=<  (~(urn by netwerk) network-to-json)                 :: I think I just misunderstood how +-urn:by works.

|%
++  network  (map @p (set @p))
::
++  netwerk
  ^-  network
  %-  ~(gas by *(map @p (set @p)))
  :~  [~lorrem-mipsum (~(gas in *(set @p)) ~zod ~syx ~sev ~ten ~lev ~wel ~)]
      [~tonlur-sarret (~(gas in *(set @p)) ~zod ~syx ~sev ~ten ~lev ~wel ~)]
  ==
::
++  network-to-json
  |=  a/(pair @p (set @p))
  ^-  json
  %-  jobe
  ^-  (list {p/@t q/json})
  :~  :-  `@t`(scot %p p.a)
          ^-  json
          :-  %a
          ^-  (list json)
          %+  turn  (~(tap in q.a))
          |=  friend/@p
          [%s `@t`(scot %p friend)]
  ==
::
--


gave me this:

> +mesh-gen
{ [ p=~tonlur-sarret
      q
    [ %o
        p
      { [ p='~tonlur-sarret'
          q=[%a p=~[[%s p='~wel'] [%s p='~lev'] [%s p='~ten'] [%s p='~syx'] [%s p='~zod'] [%s p='~sev']]]
        ]
      }
    ]
  ]
  [ p=~lorrem-mipsum
      q
    [ %o
        p
      { [ p='~lorrem-mipsum'
          q=[%a p=~[[%s p='~wel'] [%s p='~lev'] [%s p='~ten'] [%s p='~syx'] [%s p='~zod'] [%s p='~sev']]]
        ]
      }
    ]
  ]
}

*Notice how the `p` values are @p, not @t (which is needed for ++jobe to convert to JSON).*

And then trying to `urb.bind` to my :mesh app gives me this stack trace:

exit
  /~lorrem-mipsum/home/~2017.4.18..18.33.53..14b7/arvo/hoon
  <[11.103 15].[11.134 57]>
  /~lorrem-mipsum/home/~2017.4.18..18.33.53..14b7/arvo/hoon
  <[11.104 15].[11.134 57]>
  /~lorrem-mipsum/home/~2017.4.18..18.33.53..14b7/arvo/hoon
  <[11.105 15].[11.134 57]>
  /~lorrem-mipsum/home/~2017.4.18..18.33.53..14b7/arvo/hoon
  <[11.107 15].[11.134 57]>
  /~lorrem-mipsum/home/~2017.4.18..18.33.53..14b7/arvo/hoon
  <[11.109 15].[11.134 57]>
  /~lorrem-mipsum/home/~2017.4.18..18.33.53..14b7/arvo/hoon
  <[11.109 29].[11.109 44]>
  /~lorrem-mipsum/home/~2017.4.18..18.33.53..14b7/arvo/hoon
  <[11.174 3].[11.179 13]>
  /~lorrem-mipsum/home/~2017.4.18..18.33.53..14b7/arvo/hoon
  <[11.176 3].[11.179 13]>
  /~lorrem-mipsum/home/~2017.4.18..18.33.53..14b7/arvo/hoon
  <[11.177 3].[11.179 13]>
  /~lorrem-mipsum/home/~2017.4.18..18.33.53..14b7/arvo/hoon
  <[11.178 5].[11.178 47]>
[%swim-take-vane %e %unto ~]
/~lorrem-mipsum/home/~2017.4.18..18.33.53..14b7/arvo/eyre:<[2.005 3].[2.017 13]>
/~lorrem-mipsum/home/~2017.4.18..18.33.53..14b7/arvo/eyre:<[2.006 3].[2.017 13]>
/~lorrem-mipsum/home/~2017.4.18..18.33.53..14b7/arvo/eyre:<[2.007 3].[2.017 13]>
/~lorrem-mipsum/home/~2017.4.18..18.33.53..14b7/arvo/eyre:<[2.008 3].[2.017 13]>
/~lorrem-mipsum/home/~2017.4.18..18.33.53..14b7/arvo/eyre:<[2.009 3].[2.017 13]>
/~lorrem-mipsum/home/~2017.4.18..18.33.53..14b7/arvo/eyre:<[2.010 3].[2.017 13]>
/~lorrem-mipsum/home/~2017.4.18..18.33.53..14b7/arvo/eyre:<[2.011 3].[2.017 13]>
/~lorrem-mipsum/home/~2017.4.18..18.33.53..14b7/arvo/eyre:<[2.012 3].[2.017 13]>
/~lorrem-mipsum/home/~2017.4.18..18.33.53..14b7/arvo/eyre:<[2.013 3].[2.017 13]>
/~lorrem-mipsum/home/~2017.4.18..18.33.53..14b7/arvo/eyre:<[2.014 3].[2.017 13]>
/~lorrem-mipsum/home/~2017.4.18..18.33.53..14b7/arvo/eyre:<[2.015 5].[2.016 64]>
/~lorrem-mipsum/home/~2017.4.18..18.33.53..14b7/arvo/eyre:<[2.016 5].[2.016 64]>
/~lorrem-mipsum/home/~2017.4.18..18.33.53..14b7/arvo/eyre:<[748 5].[889 7]>
/~lorrem-mipsum/home/~2017.4.18..18.33.53..14b7/arvo/eyre:<[749 5].[889 7]>
/~lorrem-mipsum/home/~2017.4.18..18.33.53..14b7/arvo/eyre:<[750 5].[889 7]>
/~lorrem-mipsum/home/~2017.4.18..18.33.53..14b7/arvo/eyre:<[752 5].[889 7]>
/~lorrem-mipsum/home/~2017.4.18..18.33.53..14b7/arvo/eyre:<[772 7].[786 9]>
/~lorrem-mipsum/home/~2017.4.18..18.33.53..14b7/arvo/eyre:<[773 7].[786 9]>
/~lorrem-mipsum/home/~2017.4.18..18.33.53..14b7/arvo/eyre:<[774 7].[786 9]>
/~lorrem-mipsum/home/~2017.4.18..18.33.53..14b7/arvo/eyre:<[780 9].[783 64]>
/~lorrem-mipsum/home/~2017.4.18..18.33.53..14b7/arvo/eyre:<[783 9].[783 64]>
/~lorrem-mipsum/home/~2017.4.18..18.33.53..14b7/arvo/eyre:<[783 40].[783 63]>
%hard
[%dead-request ~[//http/0v18.imma8/43/1]]

which makes sense since it's not valid JSON. (but should this still crash in %eyre?)

But running this generator:

/?  310
::
!:
::
:-  %say  |=  *
:-  %noun
=<  %+  turn  (~(tap by netwerk))  network-to-json      :: Changed; this works.

|%
++  network  (map @p (set @p))
::
++  netwerk
  ^-  network
  %-  ~(gas by *(map @p (set @p)))
  :~  [~lorrem-mipsum (~(gas in *(set @p)) ~zod ~syx ~sev ~ten ~lev ~wel ~)]
      [~tonlur-sarret (~(gas in *(set @p)) ~zod ~syx ~sev ~ten ~lev ~wel ~)]
  ==
::
++  network-to-json
  |=  a/(pair @p (set @p))
  ~&  a
  ^-  json
  %-  jobe
  ^-  (list {p/@t q/json})
  :~  :-  `@t`(scot %p p.a)
          ^-  json
          :-  %a
          ^-  (list json)
          %+  turn  (~(tap in q.a))
          |=  friend/@p
          [%s `@t`(scot %p friend)]
  ==
::
--


gave me what I wanted originally:

> +mesh-gen
~[
  [ %o
      p
    { [ p='~lorrem-mipsum'
        q=[%a p=~[[%s p='~wel'] [%s p='~lev'] [%s p='~ten'] [%s p='~syx'] [%s p='~zod'] [%s p='~sev']]]
      ]
    }
  ]
  [ %o
      p
    { [ p='~tonlur-sarret'
        q=[%a p=~[[%s p='~wel'] [%s p='~lev'] [%s p='~ten'] [%s p='~syx'] [%s p='~zod'] [%s p='~sev']]]
      ]
    }
  ]
]

and I can get that from the browser in my :mesh app via an `urb.bind` with this mesh.hoon:

!:
|%
++  network  (map @p (set @p))
++  netwerk
  ^-  network
  %-  ~(gas by *(map @p (set @p)))
  :~  [~lorrem-mipsum (~(gas in *(set @p)) ~zod ~syx ~sev ~ten ~lev ~wel ~)]
      [~tonlur-sarret (~(gas in *(set @p)) ~zod ~syx ~sev ~ten ~lev ~wel ~)]
  ==
::
--
::
!:
|_  {bow/bowl net/network}
::
++  prep  _`.
::
++  network-to-json
  |=  a/(pair @p (set @p))
  ~&  a
  ^-  json
  %-  jobe
  ^-  (list {p/@t q/json})
  :~  :-  `@t`(scot %p p.a)
          ^-  json
          :-  %a
          ^-  (list json)
          %+  turn  (~(tap in q.a))
          |=  friend/@p
          [%s `@t`(scot %p friend)]
  ==
::
++  peek
  |=  {our/ship pax/path}
  :-  %json
  `json`[%a %+  turn  (~(tap by netwerk))  network-to-json
::
++  peer
  |=  pax/path
  ?^  pax  `+>
  [[ost.bow %diff (peek src.bow pax)]~ +>]
::
--