Urbit/Documentation/Arvo/Clay

Scry Reference

The various Clay scries are specified by a care, which is a single character corresponding with a Clay submodule. Apart from %s they just take a path to a desk, file or directory. All examples are dojo commands, the ='s in the path are automatically populated by the dojo like:

> /===
[~.~zod ~.home ~.~2021.4.26..02.29.03..d31b ~]

Contents

  • %a - Build a hoon file.
  • %b - Dynamic mark.
  • %c - Dynamic mark conversion.
  • %d - List desks.
  • %e - Static mark.
  • %f - Static mark conversion.
  • %p - File permissions.
  • %r - Vase-wrapped file data.
  • %s - Miscellaneous scries:
    • %yaki - yaki:clay of the specified commit.
    • %blob - blob:clay of file.
    • %hash - Content hash of the specified commit.
    • %cage - cage of the data of a file.
    • %open - Compile prelude of file.
    • %late - Most recent case of desk.
    • %base - Mergebase of two desks.
  • %t - List files in directory.
  • %u - Check for existence of file.
  • %v - Desk state.
  • %w - Revision number of the given desk case.
  • %x - Raw data of file.
  • %y - arch of a file or directory.
  • %z - Content hash of a file or directory.

%a

A scry with a care of %a will build a hoon file and return it as a vase.

Example:

.^(vase %ca /===/lib/strandio/hoon)

%b

A scry with a care of %b will produce a dais:clay processed mark core for the specified mark. The path in the scry is a mark.

Example:

.^(dais:clay %cb /===/txt)

%c

A scry with a care of %c will produce a tube:clay dynamically typed mark conversion gate. The path specifies two marks - from and to, like /txt/noun.

Example:

> =a .^(tube:clay %cc /===/txt/mime)
> !<  mime  (a !>(~['foo']))
[p=/text/plain q=[p=3 q=7.303.014]]

%d

A scry with a care of %d will return a (set desk) of the desks that exist on your ship.

Example:

> .^((set desk) %cd /===)
{%home %kids}

%e

A scry with a care of %e will return a statically typed nave:clay mark core in a vase. The path in the scry specifies the mark.

Example:

.^(vase %ce /===/noun)

%f

A scry with a care of %f will return a static mark conversion gate. The path specifies two marks - from and to, like /txt/mime.

> =a .^($-(text mime) %cf /===/txt/mime)
> (a ~['foo'])
[p=/text/plain q=[p=3 q=7.303.014]]

%p

A scry with a care of %p will return the permissions of the file or directory in question. The type returned is a [dict:clay dict:clay] where the head is read permissions and the tail is write permissions.

If the specified file or directory has no permissions set, it will default to the permissions of its parent. If nothing above it has permissions set, it will default to empty whitelists. If the specified file or directory doesn't exist, it will also return the default empty whitelist.

Example:

> .^([dict:clay dict:clay] %cp /===/gen)
[[src=/ rul=[mod=%white who=[p={} q={}]]] src=/ rul=[mod=%white who=[p={} q={}]]]

%r

A scry with a care of %r will return the data of the given file wrapped in a vase or crash if it's a directory. It's basically just a vase-wrapped %x scry.

Examples:

> .^(vase %cr /===/gen/hood/hi/hoon)
[ #t/@
    q
  3.548.750.706.400.251.607.252.023.288.575.526.190.856.734.474.077.821.289.791.377.301.707.878.697.553.411.219.689.905.949.957.893.633.811.025.757.107.990.477.902.858.170.125.439.223.250.551.937.540.468.638.902.955.378.837.954.792.031.592.462.617.422.136.386.332.469.076.584.061.249.923.938.374.214.925.312.954.606.277.212.923.859.309.330.556.730.410.200.952.056.760.727.611.447.500.996.168.035.027.753.417.869.213.425.113.257.514.474.700.810.203.348.784.547.006.707.150.406.298.809.062.567.217.447.347.357.039.994.339.342.906
]
> !<  @t  .^(vase %cr /===/gen/hood/hi/hoon)
'::  Helm: send message to an urbit\0a::\0a::::  /hoon/hi/hood/gen\0a  ::\0a/?    310\0a:-  %say\0a|=([^ [who=ship mez=$@(~ [a=tape ~])] ~] helm-send-hi+[who ?~(mez ~ `a.mez)])\0a'
> .^(vase %cr /===/gen)
Crash!

%s

A scry with a care of %s is for miscellaneous internal and debug functions and is liable to change in the future.

Rather than just a path to a file, the head of the path is tagged with one of %yaki %blob %hash %cage %open %late %base and the tail depends on which tag you use. We'll look at each in turn.

%yaki

This will return the yaki:clay of the specified commit. It takes a tako:clay.

Example:

Here we scry the dome:clay for /===, get the latest tako:clay and the do a %s scry for the yaki:clay in question.

> =/  =dome:clay  .^(dome:clay %cv /===)
  =/  =tako:clay  (~(got by hit.dome) let.dome)
  .^(yaki:clay %cs /===/yaki/(scot %uv tako))
[ p=~[80.174.473.756.485.530.520.259.753.935.584.637.641.665.425.899.348.092.348.244.635.557.986.495.151.006]
    q
  { [p=/mar/hark/graph-hook-update/hoon q=0v5.ea0bj.21s5c.mjrop.ishic.fpkvl.e5bbs.91kc9.tdo41.ifi06.60v41]
    [p=/gen/hood/autocommit/hoon q=0v19.rh7jv.sa67o.t3jrb.4sdvs.7c45f.pv2u0.ragik.psp20.agqd8.8srkj]
    ...
    [p=/tests/lib/primitive-rsa/hoon q=0v1g.3qmq3.6i15q.arh6h.lfsqu.gvc9m.ql6m5.e2rdr.vnnt9.tptc6.mv9u7]
    [p=/tests/sys/vane/gall/hoon q=0va.alspc.qptqn.7tuj0.bgecg.1093t.gtsjs.up03k.d1fmk.4jrh8.2tdfa]
  }
  r=88.666.797.531.755.181.802.690.473.856.185.443.710.929.766.582.249.039.904.824.278.074.149.777.897.099
  t=~2021.4.16..10.41.57..3565
]

%blob

This will return the blob:clay of some file. It takes a lobe:clay.

Example:

Here we grab the lobe:clay of /gen/hood/hi/hoon with a %y scry, then use it to do a %s scry for the blob:clay of the file.

> =/  =arch  .^(arch %cy /===/gen/hood/hi/hoon)
  ?~  fil.arch
    ~
  .^(blob:clay %cs /===/blob/(scot %uv u.fil.arch))
[ %direct
  p=0vp.k7nsm.qkdr3.t17rp.33bae.8gajg.v27gi.40itr.2u9qa.nppbt.7k255
    q
  [ p=%hoon
      q
3.548.750.706.400.251.607.252.023.288.575.526.190.856.734.474.077.821.289.791.377.301.707.878.697.553.411.219.689.905.949.957.893.633.811.025.757.107.990.477.902.858.170.125.439.223.250.551.937.540.468.638.902.955.378.837.954.792.031.592.462.617.422.136.386.332.469.076.584.061.249.923.938.374.214.925.312.954.606.277.212.923.859.309.330.556.730.410.200.952.056.760.727.611.447.500.996.168.035.027.753.417.869.213.425.113.257.514.474.700.810.203.348.784.547.006.707.150.406.298.809.062.567.217.447.347.357.039.994.339.342.906
  ]
]

%hash

This will return the @uvI content hash of the specified commit. It takes a tako:clay.

Example:

Here we grab the dome:clay for /=== with a %v scry, get the latest tako:clay and then do a %s %hash scry for it.

> =/  =dome:clay  .^(dome:clay %cv /===)
  =/  =tako:clay  (~(got by hit.dome) let.dome)
  .^(tako:clay %cs /===/hash/(scot %uv tako))
0v16.er7uq.oke4u.cru7u.nglu9.q3su7.6ub1o.bh4qk.r5uav.ut12d.5rdl5

%cage

This will return a cage of the data of some file. It takes a lobe:clay.

Example:

Here we grab the lobe:clay of /gen/hood/hi/hoon with a %y scry, then use it to do a %s scry for the cage of the data.

> =/  =arch  .^(arch %cy /===/gen/hood/hi/hoon)
  ?~  fil.arch
    ~
  .^(cage %cs /===/cage/(scot %uv u.fil.arch))
[ p=%hoon
    q
  [ #t/@t
      q
3.548.750.706.400.251.607.252.023.288.575.526.190.856.734.474.077.821.289.791.377.301.707.878.697.553.411.219.689.905.949.957.893.633.811.025.757.107.990.477.902.858.170.125.439.223.250.551.937.540.468.638.902.955.378.837.954.792.031.592.462.617.422.136.386.332.469.076.584.061.249.923.938.374.214.925.312.954.606.277.212.923.859.309.330.556.730.410.200.952.056.760.727.611.447.500.996.168.035.027.753.417.869.213.425.113.257.514.474.700.810.203.348.784.547.006.707.150.406.298.809.062.567.217.447.347.357.039.994.339.342.906
  ]
]

%open

This is like a %a scry but it only compiles the prelude to the file, e.g. the Ford rune imports. Proper documentation for this will be done as part of Ford documentaton at a later date.

%late

This will return the most recent revision number of a desk that has been fully downloaded. The type it returns is a cass:clay. The case in the beak must be a revision number rather than a date. You can just provide a case of 1 since it returns the latest regardless. If we have nothing for the specified desk, this will just return the bunt of a cass:clay like cass=[ud=0 da=~2000.1.1].

Example:

> .^(=cass:clay %cs /(scot %p (sein:title our now our))/kids/1/late)
cass=[ud=50 da=~2021.4.22..10.38.50..57a8]
> .^(=cass:clay %cs /~sampel/kids/1/late)
cass=[ud=0 da=~2000.1.1]

%base

This will return the mergebase (i.e. most recent common ancestor) between two desks. The type it returns is a (list tako:clay). The first desk will just be the one in the beak path prefix and the second will be specified like /ship/desk at the end of the scry path. If there is no common ancestor between the two desks, this will just produce an empty list.

Examples:

> .^((list tako:clay) %cs /===/base/(scot %p (sein:title our now our))/kids)
~[102.787.244.596.033.419.950.995.540.301.493.841.569.518.772.322.508.085.465.561.801.703.148.627.263.473]
> .^((list tako:clay) %cs /===/base/~sampel/kids)
~

%t

A scry with a care of %t will return a (list path) of all files in the given directory, or just a (list path) of the single file if it's a file. This is done recursively so will provide files in subdirectories as well. The paths will be fully qualified except for the ship, desk and case. If the directory or file specified does not exist, it will return an empty list.

Examples:

> .^((list path) %ct /===/app/landscape)
~[
  /app/landscape/css/index/css
  /app/landscape/img/favicon/png
  /app/landscape/img/imageupload/png
  /app/landscape/img/touch_icon/png
  /app/landscape/index/html
  /app/landscape/js/channel/js
]
> .^((list path) %ct /===/gen/group-store/add/hoon)
~[/gen/group-store/add/hoon]
> .^((list path) %ct /===/foobar)
~

%u

A scry with a care of %u will return a ? depending on whether the file exists. It will produce %.n if it's a directory or doesn't exist and will produce %.y if it's a file and exists.

Examples:

> .^(? %cu /===/app)
%.n
> .^(? %cu /===/gen/code/hoon)
%.y
> .^(? %cu /===/foobar)
%.n

%v

A scry with a care of %v will return the entire state of a desk as a dome:clay.

Example:

> =a .^(dome:clay %cv /===)
> let.a
1

Note: If you try printing this it will take forever and probably OOM your ship.

%w

A scry with a care of %w will return the revision number and date of a given case. The type returned is a cass:clay like [ud=@ud da=@da] where ud is the revision number and da is the date.

Example:

> .^(cass:clay %cw /===)
[ud=2 da=~2021.4.13..19.12.49..3389]

%x

A scry with a care of %x will return the raw data of a file as an @ or crash if it's a directory.

Examples:

> .^(@ %cx /===/gen/hood/hi/hoon)
3.548.750.706.400.251.607.252.023.288.575.526.190.856.734.474.077.821.289.791.377.301.707.878.697.553.411.219.689.905.949.957.893.633.811.025.757.107.990.477.902.858.170.125.439.223.250.551.937.540.468.638.902.955.378.837.954.792.031.592.462.617.422.136.386.332.469.076.584.061.249.923.938.374.214.925.312.954.606.277.212.923.859.309.330.556.730.410.200.952.056.760.727.611.447.500.996.168.035.027.753.417.869.213.425.113.257.514.474.700.810.203.348.784.547.006.707.150.406.298.809.062.567.217.447.347.357.039.994.339.342.906
> .^(@t %cx /===/gen/hood/hi/hoon)
'::  Helm: send message to an urbit\0a::\0a::::  /hoon/hi/hood/gen\0a  ::\0a/?    310\0a:-  %say\0a|=([^ [who=ship mez=$@(~ [a=tape ~])] ~] helm-send-hi+[who ?~(mez ~ `a.mez)])\0a'
> .^(@ %cx /===/gen/hood)
Crash!

%y

A scry with a care of %y will return the arch of a file or directory.

An arch is a [fil=(unit lobe:clay) dir=(map @ta ~)]. The fil will contain the lobe:clay hash if it's a file, otherwise it will be null. The dir will contain a map of the files and directories it contains, otherwise it will be null.

It will return the bunt of an arch if the file or directory is not found.

Examples:

> .^(arch %cy /===/gen/group-store)
[ fil=~
    dir
  { [p=~.allow-ships q=~]
    [p=~.add q=~]
    [p=~.ban-ranks q=~]
    [p=~.remove q=~]
    [p=~.create q=~]
    [p=~.join q=~]
    [p=~.allow-ranks q=~]
    [p=~.ban-ships q=~]
  }
]
> .^(arch %cy /===/gen/group-store/allow-ships)
[fil=~ dir={[p=~.hoon q=~]}]
> .^(arch %cy /===/gen/group-store/allow-ships/hoon)
[fil=[~ 0vb.g8sqs.7gjm9.bl3vu.nk677.h5be1.g9eg3.4v1jo.00ivf.g8ndu.48a53] dir={}]
> .^(arch %cy /===/foobar)
[fil=~ dir={}]

%z

A scry with a care of %z will return the hash of a file or the recursive hash of a directory. If the file or directory doesn't exist it will return a null value.

The type returned is a @uxI.

Examples:

> .^(@uvI %cz /===/gen)
0v5.itmhj.lt7ak.lgr1k.dr7vu.u7u9s.ko5rf.idfcr.ukrd2.t088n.3ml1k
> .^(@uvI %cz /===/gen/code/hoon)
0v1t.vi1pf.3ba4n.87g6h.dcc1p.4t4l8.rm6a9.b4de4.v77qc.p9dc0.p8289
> .^(@uvI %cz /===/foobar)
0v0

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