80   $ hg stack -Tjson | python -m json.tool

    81   [

    82       {

    83           "isentry": true,

    84           "topic.stack.desc": "c_f",

    85           "topic.stack.index": 4,

    86           "topic.stack.state": [

    87               "current"

    88           ],

    89           "topic.stack.state.symbol": "@"

    90       },

    91       {

    92           "isentry": true,

    93           "topic.stack.desc": "c_e",

    94           "topic.stack.index": 3,

    95           "topic.stack.state": [

    96               "clean"

    97           ],

    98           "topic.stack.state.symbol": ":"

    99       },

   100       {

   101           "isentry": true,

   102           "topic.stack.desc": "c_d",

   103           "topic.stack.index": 2,

   104           "topic.stack.state": [

   105               "clean"

   106           ],

   107           "topic.stack.state.symbol": ":"

   108       },

   109       {

   110           "isentry": true,

   111           "topic.stack.desc": "c_c",

   112           "topic.stack.index": 1,

   113           "topic.stack.state": [

   114               "clean"

   115           ],

   116           "topic.stack.state.symbol": ":"

   117       },

   118       {

   119           "isentry": false,

   120           "topic.stack.desc": "c_b",

   121           "topic.stack.state": [

   122               "base"

   123           ],

   124           "topic.stack.state.symbol": "^"

   125       }

   126   ]

   185   $ hg up t3

   186   2 files updated, 0 files merged, 0 files removed, 0 files unresolved

   187   $ hg topic --list

   188   ### topic: foo

   189   ### branch: default

   190   t4$ c_f (unstable)

   191   t3@ c_e (current)

   192   t2: c_d

   193   t1: c_c

   194     ^ c_b

   195   $ hg topic --list --color=debug

   196   [topic.stack.summary.topic|### topic: [topic.active|foo]]

   197   [topic.stack.summary.branches|### branch: default]

   198   [topic.stack.index topic.stack.index.unstable|t4][topic.stack.state topic.stack.state.unstable|$] [topic.stack.desc topic.stack.desc.unstable|c_f][topic.stack.state topic.stack.state.unstable| (unstable)]

   199   [topic.stack.index topic.stack.index.current|t3][topic.stack.state topic.stack.state.current|@] [topic.stack.desc topic.stack.desc.current|c_e][topic.stack.state topic.stack.state.current| (current)]

   200   [topic.stack.index topic.stack.index.clean|t2][topic.stack.state topic.stack.state.clean|:] [topic.stack.desc topic.stack.desc.clean|c_d]

   201   [topic.stack.index topic.stack.index.clean|t1][topic.stack.state topic.stack.state.clean|:] [topic.stack.desc topic.stack.desc.clean|c_c]

   202     [topic.stack.state topic.stack.state.base|^] [topic.stack.desc topic.stack.desc.base|c_b]

   203   $ hg up t2

   204   1 files updated, 0 files merged, 1 files removed, 0 files unresolved