Urbit/Documentation/Hoon/Reference/Standard library

2q: Molds and Mold-Builders

++char

Character

A single character. Aura @tD designates a single UTF-8 byte. All parsers consume tapes, which are lists of char.

Source

++  char  @tD

Examples

    > *char
    ''

    > `@tD`97
    'a'

++cord

UTF-8 text

One of Hoon's two string types (the other being tape). A cord is an atom of UTF-8 text.

Source

++  cord  @t

Examples

    > *cord
    ''

    > `@ux`'foobar'
    0x7261.626f.6f66

    > `@t`97
    'a'

    > `@`'urbit'
    499.984.265.845

    > `@t`499.984.265.845
    'urbit'

Discussion

Aura @t designates a Unicode atom, little-endian: the first character in the text is the least-significant byte.

trip converts from cord to tape, and crip converts from tape to cord.

++date

Point in time

A boolean designating AD or BC, a year atom, a month atom, and a tarp, which is a day atom and a time.

Source

++  date  [[a=? y=@ud] m=@ud t=tarp]

Examples

    > *date
    [[a=%.y y=0] m=0 t=[d=0 h=0 m=0 s=0 f=~]]

    > `date`(yore ~2014.6.6..21.09.15..0a16)
    [[a=%.y y=2.014] m=6 t=[d=6 h=21 m=9 s=15 f=~[0xa16]]]

    > now
    ~2018.5.25..17.55.15..9ad8

Discussion

See also: year, yore

++knot

ASCII

An atom type that only permits ASCII characters.

Source

++  knot  @ta

Examples

    > *knot
    ~.

    > `@ta`105
    ~.i

++tang

Generic print structure

A list of tanks. It's for printing types and bottom-up printing of stack traces.

Source

++  tang  (list tank)

Examples

    > *tang
    ~

    > (~(win re [%palm ["1" "2" "3" "4"] [%leaf "foobar"] [%leaf "bazbud"] [%leaf "zzzzzzqaaa"] ~]) 0 50)
    <<"23foobar1bazbud1zzzzzzqaaa4">>

    > (~(win re [%palm ["1" "2" "3" "4"] [%leaf "foobar"] [%leaf "bazbud"] [%leaf "zzzzzzqaaa"] ~]) 0 10)
    <<"2   foobar" "  bazbud" "zzzzzzqaaa">>

    > (~(win re [%rose ["1" "2" "3"] [%leaf "foobar"] [%leaf "bazbud"] ~]) 0 20)
    <<"2foobar1bazbud3">>

    > (~(win re [%rose ["1" "2" "3"] [%leaf "foobar"] [%leaf "bazbud"] ~]) 0 10)
    <<"2 foobar" "  bazbud" "3">>

++tank

Pretty-printing structure

A tank is one of three cases: a %leaf is simply a string (a printed line); a %palm is list of tank delimited by the strings in p, with back-steps at new lines; and a %rose is a list of tank delimited by the strings in p without back-steps at new lines.

Source

++  tank  $%  [$leaf p=tape]
                  $:  $palm
                      p=[p=tape q=tape r=tape s=tape]
                      q=(list tank)
                  ==
                  $:  $rose
                      p=[p=tape q=tape r=tape]
                      q=(list tank)
                  ==
              ==

Examples

    > *tank
    [%rose p=[p="" q="" r=""] q=~]

    > (wash [0 80] >(bex 20) (bex 19)<)                               :: at 80 cols
    <<"[1.048.576 524.288]">>

    > (wash [0 15] >(bex 20) (bex 19)<)                               :: at 15 cols
    <<"[ 1.048.576" "  524.288" "]">>

    > [(bex 150) (bex 151)]                                           :: at 80 cols
    [ 1.427.247.692.705.959.881.058.285.969.449.495.136.382.746.624
      2.854.495.385.411.919.762.116.571.938.898.990.272.765.493.248
    ]

    > (wash [0 40] >(bex 150) (bex 151)<)
    <<
      "[ \\/1.427.247.692.705.959.881.058.285.\\/"
      "    969.449.495.136.382.746.624"
      "  \\/                                  \\/"
      "  \\/2.854.495.385.411.919.762.116.571.\\/"
      "    938.898.990.272.765.493.248"
      "  \\/                                  \\/"
      "]"
    >>

++tape

List of characters

One of Hoon's two string types, the other being ++cord. A tape is a list of char.

Source

++  tape  (list @tD)

Examples

    > *tape
    ""

    > `tape`"foobar"
    "foobar"

    >`(list @t)`"foobar"
    <|f o o b a r|>

    >`(list @tD)`"foobar"
    "foobar"

    > `(list @)`"foobar"
    ~[102 111 111 98 97 114]

++tarp

Parsed time

The time component of a date: day, hour, minute, second and a list of @ux for precision.

Source

++  tarp  [d=@ud h=@ud m=@ud s=@ud f=(list @ux)]

Examples

    > *tarp
    [d=0 h=0 m=0 s=0 f=~]

    > (yell now)
    [d=106.751.991.821.625 h=22 m=58 s=10 f=~[0x44ff]]

    > `tarp`(yell ~2014.6.6..21.09.15..0a16)
    [d=106.751.991.820.172 h=21 m=9 s=15 f=~[0xa16]]

    > (yell ~d20)
    [d=20 h=0 m=0 s=0 f=~]

++term

Hoon constant

A restricted text atom for Hoon constants. The only characters permitted are lowercase ASCII letters, -, and 0-9, the latter two of which cannot be the first character. The syntax for @tas is the text itself, always preceded by %. The empty @tas has a special syntax, $.

Source

++  term  @tas

Examples

    > *term
    %$

    > *%term
    %term

    > %dead-fish9
    %dead-fish9

    > -:!>(%dead-fish9)
    #t/$dead-fish9

++wain

List of strings

A list of cords. A wain is used instead of a single cord with \n.

Source

++  wain  (list cord)

Examples

    > *wain
    <||>

    > `wain`/som/del/rok
    <|som del rok|>

++wall

List of list of characters

A list of tapes. wall is used instead of a single tape with \n.

Source

++  wall  (list tape)

Examples

    > *wall
    <<>>

    > `wall`(wash [0 20] leaf+<(bex 256)>)
    <<
      "\\/115.792.089.237.\\/"
      "  316.195.423.570."
      "  985.008.687.907."
      "  853.269.984.665."
      "  640.564.039.457."
      "  584.007.913.129."
      "  639.936"
      "\\/                \\/"
    >>

<-

2p: Serialization

3a: Modular and Signed Ints

->