0407872 · urbit.org · git.iko.soy

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Merge branch 'master' of github.com:urbit/docs

0407872Tobias Merkle10 years ago

docs.md+38−12

compare with master

unifiedsplit

@@ -1,7 +1,7 @@

1---

2anchor: none

3footer: true

4−title: Develop

4+title: Documentation

5sort: 4

6---

@@ -10,21 +10,47 @@ sort: 4

10 <h1 class="blue i-b">Urbit docs</h1>

11</div>

13−Go to the [technical overview](about/overview) for a high-level

13+<div class="col-md-12 head">

14−architecture description. To install and run Urbit, read forward from the

15−[installation guide](using/install).

15+<div class="col-md-8">

16+

17+Check out the [technical overview](about/overview) for a high-level

18+architecture description. To install and run Urbit, head to the Using section, starting with the [installation guide](using/install) and continuing forward.

19+

17−To begin developing for Urbit, start by learning Hoon [syntax](hoon/syntax),

20+To begin developing for Urbit, start by learning Hoon [syntax](hoon/syntax),

18−then walk through the [Arvo tutorials](arvo). The examples and exercises

21+then walk through the [Arvo tutorials](arvo). The examples and exercises

19−in Arvo will teach you to build high-level programs and interact with the network.

22+in Arvo will teach you to build high-level programs and interact with the network.

21Dig into the mechanics of Urbit with [Core Hoon](hoon). Refer back

24Dig into the mechanics of Urbit with [Core Hoon](hoon). Refer back

22−there for pure-code exercises and functions in the [standard library](hoon/library).

25+there for pure-code exercises and functions in the [standard library](hoon/library).

26+

27+Registered academics are required to start with the [Nock definition](nock/definition) and work upward from there.

28+

29+</div>

30+

31+<div class="col-md-4">

24−Registered academics are required to start with the [Nock definition](nock/definition)

33+<b>Source on GitHub</b>

25−and work upward from there.

34+<ul>

26−<br/>

35+<li><a href="https://github.com/urbit/urbit">Main repo</a></li>

27−<br/>

36+<li><a href="https://github.com/urbit/examples">Examples</a></li>

37+<li><a href="https://github.com/urbit/docs">Documentation</a></li>

38+</ul>

39+

40+<br />

41+

42+<b>Community / contact</b>

43+<ul>

44+<li>We use <code>:talk</code> on Urbit to chat.</li>

45+<li><a href="https://reddit.com/r/urbit">/r/urbit on Reddit</a></li>

46+<li><a href="https://twitter.com/urbit_">@urbit_ on Twitter</a></li>

47+<li><a href="https://groups.google.com/forum/#!forum/urbit-dev">urbit-dev mailing list</a></li>

48+<li><a href="mailto:urbit@urbit.org">urbit@urbit.org</a></li>

49+</ul>

50+

51+</div>

52+

53+</div>

29<div class="sections">

55<div class="sections">

30 <kids grid="true"></kids>

56 <kids grid="true"></kids>

docs/arvo.md+6−2

@@ -1,8 +1,12 @@

1---

2navhome: /docs

3−sort: 4

3+sort: 3

4---

6−# Arvo

6+# Arvo programming

8+This example-based sequence of tutorials shows you how to build simple programs in hoon and use the basic features of Arvo.

10+If you like to learn by example, start here.

8<list/>

12<list/>

docs/arvo/basic.md+2−2

@@ -23,8 +23,8 @@ To run this code, you'll need an urbit, and will have to copy the

23[examples repo](https://github.com/urbit/examples) into it.

25If you haven't installed urbit yet, check out the [installation

26−instructions](/docs/user/install). Once urbit is installed, take a look

26+instructions](/docs/using/install). Once urbit is installed, take a look

27−at the [basic operation](/docs/user/basic) of your urbit.

27+at the [basic operation](/docs/using/admin) of your urbit.

29If you haven't copied in the examples repo, running the following

30commands from your urbit directory should do the trick:

docs/arvo/generators.md+1−1

@@ -15,7 +15,7 @@ the "plumbing" way to interact with apps. Generators are the

15`|merge`, there are no marks in sight.

17We've used generators before, back in [Basic

18−Operation](/docs/user/basic). At that point, we just used the generators

18+Operation](/docs/using/admin). At that point, we just used the generators

19to produce values -- we didn't pipe their results into apps. In

20the dojo cast, the role of a generator is to take a list of

21arguments and produce a value, which is often, though not always,

docs/arvo/subject.md+1−1

@@ -93,7 +93,7 @@ Cheatsheet:

94- To pass arguments from the command line to a program, you replace

95 the `*` in the first line of the boiler plate to

96− `{^ {{arg/TYPE ~} ~}}` where `TYPE` is replaced with the type of

96+ `{^ {{arg/TYPE $~} $~}}` where `TYPE` is replaced with the type of

97 argument you're expecting. Then `+euler1 a` from the dojo sets `arg`

98 to `a`.

99- The empty list is `~`

docs/hoon.md+6−2

@@ -1,8 +1,12 @@

1---

2navhome: /docs

3−sort: 3

3+sort: 4

4---

6−# Hoon

6+# Hoon reference

8+This in-depth reference covers all the features of Hoon.

10+If you prefer to learn from the bottom up, feel free to start here.

8<list/>

12<list/>

docs/hoon/advanced.md+1−1

@@ -186,7 +186,7 @@ limb, we just search the span depth-first.

186If a name is in the `p.p` map, it's an alias. The map contains a

187`(unit twig)`; if the unit is full, the name resolves to that

188twig (compiled against the `q` span). If the unit is empty,

189−the name is blocked / skipped (see [limb](twig/limb) for what

189+the name is blocked / skipped (see [limb](../twig/limb) for what

190this means).

191

192If a name is in the `q.p` map, it's a bridge. When we search for

docs/hoon/exercises/data-structures.md+1−1

@@ -26,7 +26,7 @@ exercises, you'll need to refer to the [library reference for

26 `'javacript'`, `'python'`.

281. At the dojo, take the union of `s` and `l`. Delete

29− `'javascript'` from the result, and add `'coffescript'`.

29+ `'javascript'` from the result, and add `'coffeescript'`.

311. Create an alphabetized list of the members of the set created

32 in the previous exercise.

docs/hoon/library/2b.md+1−1

@@ -667,7 +667,7 @@ sorted according to `b`.

667Accepts

668-------

669

670−`b` is a gate that ccepts two nouns and produces a boolean.

670+`b` is a gate that accepts two nouns and produces a boolean.

671

672Produces

673--------

docs/hoon/library/2q.md+2−2

@@ -147,9 +147,9 @@ Source

147Examples

148--------

149

150− > `(list ,char)`"foobar"

150+ > `(list char)`"foobar"

151 "foobar"

152− > `(list ,@)`"foobar"

152+ > `(list @)`"foobar"

153 ~[102 111 111 98 97 114]

154

155

docs/hoon/reference.md+4

@@ -10,6 +10,10 @@ title: Twig reference

11<div class="book">

13+### [Atoms and strings](../twig/atom)

14+

15+### [Limbs and wings](../twig/limb)

16+

13## `$ buc` (mold)

17## `$ buc` (mold)

15<list src="../twig/buc-mold" dataPreview="true" className="runes" childIsFragment="true"></list>

19<list src="../twig/buc-mold" dataPreview="true" className="runes" childIsFragment="true"></list>

docs/hoon/twig/wut-test/gar-sure.md+1−1

@@ -3,7 +3,7 @@ navhome: /docs

3sort: 11

4---

6−# `:sure ?< "wutgar"`

6+# `:sure ?> "wutgar"`

8`{$sure p/seed q/seed}`: positive assertion.

docs/hoon/twig/zap-wild/gar-wrap.md+1−1

@@ -24,5 +24,5 @@ span-noun cell is generally called a `vase`.

25```

26~zod:dojo> !>(1)

27−[#t/@ud q=1]

27+[p=#t/@ud q=1]

28```

docs/nock.md+4

@@ -6,4 +6,8 @@ title: Nock

7# Nock

9+Nock is our nano-VM. If you're into combinators or want to understand the foundation of Urbit, dive in.

10+

11+Building a Nock interpreter is a fun exercise, as you can see in the [implementations](nock/implementations)

12+

9<list/>

13<list/>

docs/using.md+4

@@ -5,4 +5,8 @@ sort: 2

6# Using

8+These short guides will get you installed, setup, and walk you through the basic features of Urbit. Each section has a quickstart at the top that covers the basics.

10+The sections do build on eachother, so it's a good idea to at least skim them in order.

11+

8<list/>

12<list/>

docs/using/layout.md+1−1

@@ -1,6 +1,6 @@

1---

2navhome: /docs

3−sort: 8

3+sort: 9

4title: Source layout

5---

docs/using/messaging.md+4

@@ -60,6 +60,10 @@ To set your audience back to `/urbit-meta`:

61 ~your-urbit:talk> ;~doznec/urbit-meta

63+Use `;leave` to unsubscribe from a channel:

64+

65+ ~your-urbit:talk> ;leave ~doznec/urbit-meta

66+

63There are two ways of using `:talk`: from the CLI or through a web ui available at `http://your-urbit.urbit.org/talk` (or `http://localhost:8080/talk`).

67There are two ways of using `:talk`: from the CLI or through a web ui available at `http://your-urbit.urbit.org/talk` (or `http://localhost:8080/talk`).

65The web ui ships as compiled JavaScript on your Urbit, but has its own source repo [here](https://github.com/urbit/talk).

69The web ui ships as compiled JavaScript on your Urbit, but has its own source repo [here](https://github.com/urbit/talk).

docs/using/urb.mdnew file+356

@@ -0,0 +1,356 @@

1+---

2+navhome: /docs

3+sort: 8

4+title: From Unix

5+---

7+<div class="row">

8+<div class="col-md-8">

10+# Using Urbit from Unix

11+

12+With `urb` at your Unix command line, you can execute hoon, run

13+dojo commands, and more. Additionally, with `fuse`, you can

14+inspect the urbit namespace.

15+

16+</div>

17+</div>

18+

19+## Installation

20+

21+These commands are in the a [separate

22+repo](https://github.com/urbit/urb). Clone this repo to get the

23+commands.

24+

25+You'll also need the `requests` and `fuse` libraries for python.

26+If you have `pip`, you can just run:

27+

28+```

29+pip install requests fuse-python

30+```

31+

32+Otherwise, on Ubuntu, run:

33+

34+```

35+apt-get install python-requests python-fuse

36+```

37+

38+Then you can either run the python commands from the git repo, or

39+put them somewhere in your path.

40+

41+## `urb`

42+

43+`urb` transfers data from a source to a sink. Examples of data

44+sources include literal data, a file, a URL, or some

45+tranformation of another source. Examples of data sinks are

46+stdout, output file, POST request, or dojo command.

47+

48+Here are some examples. This takes the literal data "hello

49+world" and sends it to stdout (the default sink).

50+

51+ urb --data 'hello world'

52+

53+Let's run some hoon code at the dojo.

54+

55+ urb --dojo '(add 2 2)'

56+

57+Let's convert a markdown file to html.

58+

59+ urb --data @@file.md -m md -m html

60+

61+Mount the `%home` desk. This syncs the `home` desk into the pier

62+directory.

63+

64+ urb --dojo '+hood/mount /=home=' --app hood

65+

66+### Sources

67+

68+Sources can be any of the following:

69+

70+- `-d, --dojo command` runs a dojo command. This is commonly

71+ naked hoon code, but it can also be a generator, or any of the

72+ other ways the dojo gets data.

73+

74+- `-D, --data text` is literal text data, as a cord.

75+

76+- `-c, --clay path` pulls data from Urbit's filesystem.

77+

78+- `-u, --url url` pulls data from a URL.

79+

80+- `-m, --mark mark source` converts the output from another source to

81+ a new 'mark' (datatype).

82+

83+- `-H, --hoon code source` transforms the output of another

84+ source by running it through some hoon code.

85+

86+- `[source-0 source-1 ...]`. Sources can be combined into tuples

87+ of different sources.

88+

89+Any of the arguments to a source (except in the "compound

90+sources" `--mark` and `--hoon`) can be replaced by `-` to

91+represent stdin or `@@filename` to pull data in from a Unix file.

92+Thus, `urb [-D @@file1 -D - -D @@file2]` is equivalent to Unix's

93+`cat file1 - file2`.

94+

95+Additionally, if no source is specified, `--data -` (stdin as

96+literal text data) is assumed.

97+

98+### Sinks

99+

100+- `-s, --stdout` outputs to stdout. This is the default.

101+

102+- `-f, --output-file path` writes to a unix file.

103+

104+- `-C, --output-clay path` writes to Urbit's filesystem.

105+

106+- `-U, --output-url url` sends a POST request with the data to

107+ the URL.

108+

109+- `-p, --app app` sends the data to an urbit app.

110+

111+- `-x, --command` outputs to a literal dojo command.

112+

113+## `fuse`

114+

115+Urbit's namespace is accessible through the `fuse` command.

116+`fuse` takes all the normal FUSE arguments, which you can see

117+with `fuse -h`. Generally, you just run `fuse MOUNT-POINT`.

118+

119+When accessing the namespace through `fuse`, everything is

120+read-only. If you want to write to Clay, mount a desk, as

121+described above.

122+

123+Let's look first in the Clay portion of the Urbit namespace.

124+Assume we've mounted to `./pt`.

125+

126+ $ ls ./pt/c/=/=/=

127+ app arvo gen lib mar ren sec sur web

128+ $ ls ./pt/c/=/=/=/arvo

129+ ames behn clay dill eyre ford gall hoon zuse

130+

131+Those `=`s aren't decorative. The first `=` means "current

132+ship", the second "current desk", and the third "current

133+revision". Let's try something a little more exciting.

134+

135+This runs the Unix `diff` command on the first and current

136+versions of the `app/gh/hoon` file, showing all the changes we've

137+made to the file.

138+

139+```

140+$ diff pt/c/=/=/{1,=}/app/gh/hoon

141+73c73,75

142+< (malt (turn issues |=(issue:gh [(rsh 3 2 (scot %ui number)) ~])))

143+---

144+> %- malt ^- (list {@ta $~})

145+> :- [%gh-list-issues ~]

146+> (turn issues |=(issue:gh [(rsh 3 2 (scot %ui number)) ~]))

147+92c94,101

148+< read-y=(read-get /issues)

149+---

150+> read-y=(read-static %gh-list-issues ~)

151+> sigh-x=sigh-list-issues-x

152+> sigh-y=sigh-list-issues-y

153+> ==

154+> ^- place :: /issues/mine/<mark>

155+> :* guard={$issues $mine @t $~}

156+> read-x=read-null

157+> read-y=|=(pax/path [ost %diff %arch `0vsen.tinel ~])

158+126c135

159+< ^- place :: /issues/by-repo/<user>/<repo>

160+---

161+> ^- place :: /issues/by-repo/<user>/<repo>/<number>

162+131c140,146

163+< read-y=(read-static ~)

164+---

165+> ^= read-y

166+> |= pax/path

167+> %. pax

168+> ?: ((sane %tas) -.+>+>.pax)

169+> (read-static ~)

170+> (read-static %gh-issue ~)

171+> ::

172+137a153,159

173+> sigh-y=sigh-strange

174+> ==

175+> ^- place :: /issues/by-repo/<u>/<r>/<n>/<mark>

176+> :* guard={$issues $by-repo @t @t @t @t $~}

177+> read-x=read-null

178+> read-y=|=(pax/path [ost %diff %arch `0vsen.tinel ~])

179+> sigh-x=sigh-strange

180+```

181+

182+Urbit's namespace is not just revisioned, but global. Here's a

183+diff of our version of `arvo/gall/hoon` compared to the one on

184+the `~bud` urbit.

185+

186+```

187+$ diff pt/c/{~bud,=}/=/=/arvo/gall/hoon

188+2d1

189+<

190+640a640,644

191+> =+ ?. ?=($x ren)

192+> [mar=%$ tyl=tyl]

193+> =+ `path`(flop tyl)

194+> ?> ?=(^ -)

195+> [mar=i tyl=(flop t)]

196+643c647

197+< ((slog leaf+"peek find fail" >tyl< ~) [~ ~])

198+---

199+> ((slog leaf+"peek find fail" >tyl< >mar< ~) [~ ~])

200+654a659,660

201+> ?. =(mar p.q.caz)

202+> [~ ~]

203+1308a1315,1316

204+> ?. ?=(^ tyl)

205+> ~

206+```

207+

208+Besides Clay, the namespace contains Gall apps. One common usage

209+of the app namespace is to expose APIs. For example, if you

210+start the `%gh` app (`|start %gh`), you can do things like `cat`

211+an issue from a repository.

212+

213+```

214+$ cat pt/g/=/gh/=/issues/by-repo/philipcmonktest/testing/7/txt

215+title: big news! (#7)

216+state: open

217+creator: philipcmonktest

218+created-at: 2016-03-24T22:27:33Z

219+assignee: philipcmonktest

220+labels: invalid, wontfix, help wanted

221+comments: 0

222+url: https://api.github.com/repos/philipcmonktest/testing/issues/7

223+

224+Yup, that's it. i mean, maybe it's a bit longer than that.

225+

226+But you get the point, right?

227+

228+Code `is` cool!

229+```

230+

231+Or all open issues for a repository.

232+

233+```

234+$ cat pt/g/=/gh/=/issues/by-repo/philipcmonktest/testing/txt

235+title: i found a bug! (#11)

236+state: open

237+creator: philipcmonktest

238+created-at: 2016-04-14T23:14:49Z

239+assignee: none

240+labels:

241+comments: 1

242+url: https://api.github.com/repos/philipcmonktest/testing/issues/11

243+

244+

245+----------------------------------------

246+title: more newz (#8)

247+state: open

248+creator: philipcmonktest

249+created-at: 2016-03-24T22:29:16Z

250+assignee: none

251+labels:

252+comments: 4

253+url: https://api.github.com/repos/philipcmonktest/testing/issues/8

254+

255+Yup, that's it. i mean, maybe it's a bit longer than that.

256+

257+But you get the point, right?

258+

259+Code `is` cool!

260+----------------------------------------

261+title: big news! (#7)

262+state: open

263+creator: philipcmonktest

264+created-at: 2016-03-24T22:27:33Z

265+assignee: philipcmonktest

266+labels: invalid, wontfix, help wanted

267+comments: 0

268+url: https://api.github.com/repos/philipcmonktest/testing/issues/7

269+

270+Yup, that's it. i mean, maybe it's a bit longer than that.

271+

272+But you get the point, right?

273+

274+Code `is` cool!

275+----------------------------------------

276+title: something different (#4)

277+state: open

278+creator: philipcmonktest

279+created-at: 2016-01-26T21:45:08Z

280+assignee: philipcmonktest

281+labels: duplicate, help wanted, question, bug

282+comments: 1

283+url: https://api.github.com/repos/philipcmonktest/testing/issues/4

284+```

285+

286+Don't like the textual format? How about we get the raw JSON

287+(and prettyprint it).

288+

289+```

290+$ cat pt/g/=/gh/=/issues/by-repo/philipcmonktest/testing/7/json | python -m json.tool

291+{

292+ "assignee": {

293+ "avatar_url": "https://avatars.githubusercontent.com/u/16787461?v=3",

294+ "events_url": "https://api.github.com/users/philipcmonktest/events{/privacy}",

295+ "followers_url": "https://api.github.com/users/philipcmonktest/followers",

296+ "following_url": "https://api.github.com/users/philipcmonktest/following{/other_user}",

297+ "gists_url": "https://api.github.com/users/philipcmonktest/gists{/gist_id}",

298+ "gravatar_id": "",

299+ "html_url": "https://github.com/philipcmonktest",

300+ "id": 16787461,

301+ "login": "philipcmonktest",

302+ "organizations_url": "https://api.github.com/users/philipcmonktest/orgs",

303+ "received_events_url": "https://api.github.com/users/philipcmonktest/received_events",

304+ "repos_url": "https://api.github.com/users/philipcmonktest/repos",

305+ "site_admin": false,

306+ "starred_url": "https://api.github.com/users/philipcmonktest/starred{/owner}{/repo}",

307+ "subscriptions_url": "https://api.github.com/users/philipcmonktest/subscriptions",

308+ "type": "User",

309+ "url": "https://api.github.com/users/philipcmonktest"

310+ },

311+ "body": "Yup, that's it. i mean, maybe it's a bit longer than that.\r\n\r\nBut you get the point, right?\r\n\r\nCode `is` cool!",

312+ "closed_at": null,

313+ "closed_by": null,

314+ "comments": 0,

315+ "comments_url": "https://api.github.com/repos/philipcmonktest/testing/issues/7/comments",

316+ "created_at": "2016-03-24T22:27:33Z",

317+ "events_url": "https://api.github.com/repos/philipcmonktest/testing/issues/7/events",

318+ "html_url": "https://github.com/philipcmonktest/testing/issues/7",

319+ "id": 143377108,

320+ "labels": [

321+ {

322+ "color": "ffffff",

323+ "name": "wontfix",

324+ "url": "https://api.github.com/repos/philipcmonktest/testing/labels/wontfix"

325+ }

326+ ],

327+ "labels_url": "https://api.github.com/repos/philipcmonktest/testing/issues/7/labels{/name}",

328+ "locked": false,

329+ "milestone": null,

330+ "number": 7,

331+ "repository_url": "https://api.github.com/repos/philipcmonktest/testing",

332+ "state": "open",

333+ "title": "big news!",

334+ "updated_at": "2016-03-24T22:27:33Z",

335+ "url": "https://api.github.com/repos/philipcmonktest/testing/issues/7",

336+ "user": {

337+ "avatar_url": "https://avatars.githubusercontent.com/u/16787461?v=3",

338+ "events_url": "https://api.github.com/users/philipcmonktest/events{/privacy}",

339+ "followers_url": "https://api.github.com/users/philipcmonktest/followers",

340+ "following_url": "https://api.github.com/users/philipcmonktest/following{/other_user}",

341+ "gists_url": "https://api.github.com/users/philipcmonktest/gists{/gist_id}",

342+ "gravatar_id": "",

343+ "html_url": "https://github.com/philipcmonktest",

344+ "id": 16787461,

345+ "login": "philipcmonktest",

346+ "organizations_url": "https://api.github.com/users/philipcmonktest/orgs",

347+ "received_events_url": "https://api.github.com/users/philipcmonktest/received_events",

348+ "repos_url": "https://api.github.com/users/philipcmonktest/repos",

349+ "site_admin": false,

350+ "starred_url": "https://api.github.com/users/philipcmonktest/starred{/owner}{/repo}",

351+ "subscriptions_url": "https://api.github.com/users/philipcmonktest/subscriptions",

352+ "type": "User",

353+ "url": "https://api.github.com/users/philipcmonktest"

354+ }

355+}

356+```

docs/using/web.md+4−2

@@ -25,8 +25,10 @@ We ship `tree` as compiled JavaScript on your Urbit, but the source lives in its

26Your Urbit runs a web server and can be found at either `http://localhost:8080/` (or `8081` if you're running other processes that might be occupying `8080`, you can determine which port your urbit is on by looking at your boot sequence — it's specified there), or `http://your-urbit.urbit.org/`.

28+<span class="red">

28(Make sure you have a desk mounted to unix, as covered in the

29(Make sure you have a desk mounted to unix, as covered in the

29[filesystem walkthrough](/docs/using/filesystem)).

30[filesystem walkthrough](/docs/using/filesystem)).

31+</span>

31To switch the desk you're serving from:

33To switch the desk you're serving from:

@@ -38,7 +40,7 @@ To host a file on the web try putting the following in `/home/web/test.md` (from

39 This is a simple markdown file.

41 This is a simple markdown file.

41−Create the directory `/home/web/test/` and add two more markdown files in it.

43+Create the directory `/home/web/test/` and add two more markdown files in it.

43Now modify `/home/web/test.md` to list the children using the `<list/>` JSX:

45Now modify `/home/web/test.md` to list the children using the `<list/>` JSX:

@@ -56,7 +58,7 @@ To view your file as raw `html`:

57 http://localhost:8080/test.html

59 http://localhost:8080/test.html

59−You may have noticed that we just created both `test.md` and `test/`. In Urbit, there is no distinction between a directory and a file. So, if you're adding files directly from unix, simply `mkdir test` and Urbit will treat the file and directory as the same entity.

61+You may have noticed that we just created both `test.md` and `test/`. In Urbit, there is no distinction between a directory and a file. So, if you're adding files directly from unix, simply `mkdir test` and Urbit will treat the file and directory as the same entity.

61You can use this feature to change your homepage at `your-urbit.urbit.org` with the page `/home/web.md`, where `home` is the current mounted desk. By default, `web.md` will display some info about your urbit, but you can customize it to your heart's content.

63You can use this feature to change your homepage at `your-urbit.urbit.org` with the page `/home/web.md`, where `home` is the current mounted desk. By default, `web.md` will display some info about your urbit, but you can customize it to your heart's content.