6cbb6b060d
This reverts commit 8e1e40d75b3ab15c194b6bf9570f3edc46e2de58. This reverts commit f073c490f9fd7c5abc033af4857df92229877de7. This reverts commit f187d2d7e01a54823f3e979af9bbd148b398e7e9. This reverts commit bc272862a73cfce1b118586ca39d3a377d841f1b. This reverts commit 30a397513f8890a3406dc7ab91c6e067e3bbfbbb. This reverts commit 4fc6856fb50d88c20a0f533392ca606641c5f38f. Conflicts: urb/urbit.pill urb/zod/base/lib/drum.hoon
8.3 KiB
chapter 2a, basic unsigned math
++add
Add
++ add :: add
~/ %add
|= [a=@ b=@]
^- @
?: =(0 a) b
$(a (dec a), b +(b))
::
Produces the sum of a and b as an atom.
a is an atom.
b is an atom.
~zod/try=> (add 2 2)
4
~zod/try=> (add 1 1.000.000)
1.000.001
~zod/try=> (add 1.333 (mul 2 2))
1.337
++cap
Tree head
++ cap :: tree head
~/ %cap
|= a=@
^- ?(%2 %3)
?- a
%2 %2
%3 %3
?(%0 %1) !!
* $(a (div a 2))
==
::
Tests whether an a is in the head or tail of a noun. Produces the
cube %2 if it is within the head, or the cube %3 if is is
within the tail.
a is an atom.
~zod/try=> (cap 4)
%2
~zod/try=> (cap 6)
%3
~zod/try=> (cap (add 10 9))
%2
++dec
Decrement
++ dec :: decrement
~/ %dec
|= a=@
~| %decrement-underflow
?< =(0 a)
=+ b=0
|- ^- @
?: =(a +(b)) b
$(b +(b))
::
Produces a-1 as an atom.
a is an atom.
~zod/try=> (dec 7)
6
~zod/try=> (dec 0)
! decrement-underflow
! exit
++div
Divide
++ div :: divide
~/ %div
|= [a=@ b=@]
^- @
~| 'div'
?< =(0 b)
=+ c=0
|-
?: (lth a b) c
$(a (sub a b), c +(c))
::
Computes a divided by b, producing an atom.
a is an atom.
b is an atom.
~zod/try=> (div 4 2)
2
~zod/try=> (div 17 8)
2
~zod/try=> (div 20 30)
0
++fac
Factorial
++ fac :: factorial
~/ %fac
|= a=@
^- @
?: =(0 a) 1
(mul a $(a (dec a)))
::
Computes the factorial of a, producing an atom.
a is an atom.
~zod/try=> (fac 3)
6
~zod/try=> (fac 0)
1
~zod/try=> (fac 11)
39.916.800
++gte
Greater-than/equal
++ gte :: greater-equal
~/ %gte
|= [a=@ b=@]
^- ?
!(lth a b)
::
Tests whether a is greater than a number b, producing a loobean.
a is an atom.
b is an atom.
~zod/try=> (gte 100 10)
%.y
~zod/try=> (gte 4 4)
%.y
~zod/try=> (gte 3 4)
%.n
++gth
Greater-than
++ gth :: greater-than
~/ %gth
|= [a=@ b=@]
^- ?
!(lte a b)
::
Tests whether a is greater than b, producing a loobean.
a is an atom.
b is an atom.
~zod/try=> (gth 'd' 'c')
%.y
~zod/try=> (gth ~h1 ~m61)
%.n
++lte
Less-than/equal
++ lte :: less-equal
~/ %lte
|= [a=@ b=@]
|(=(a b) (lth a b))
::
Tests whether a is less than or equal to b, producing a loobean.
a is an atom.
b is an atom.
~zod/try=> (lte 4 5)
%.y
~zod/try=> (lte 5 4)
%.n
~zod/try=> (lte 5 5)
%.y
~zod/try=> (lte 0 0)
%.y
++lth
Less-than
++ lth :: less-than
~/ %lth
|= [a=@ b=@]
^- ?
?& !=(a b)
|-
?| =(0 a)
?& !=(0 b)
$(a (dec a), b (dec b))
== == ==
::
Tests whether a is less than b, producing a loobean.
a is an atom.
b is an atom.
~zod/try=> (lth 4 5)
%.y
~zod/try=> (lth 5 4)
%.n
~zod/try=> (lth 5 5)
%.n
~zod/try=> (lth 5 0)
%.n
++mas
Axis within head/tail
++ mas :: tree body
~/ %mas
|= a=@
^- @
?- a
1 !!
2 1
3 1
* (add (mod a 2) (mul $(a (div a 2)) 2))
==
::
Computes the axis of a within the head or the tail, producing an atom.
a is an atom.
~zod/try=> (mas 3)
1
~zod/try=> (mas 4)
2
~zod/try=> (mas 5)
3
~zod/try=> (mas 6)
2
~zod/try=> (mas 0)
! exit
~zod/try=> (mas 1)
! exit
++max
Maximum
++ max :: maximum
~/ %max
|= [a=@ b=@]
^- @
?: (gth a b) a
b
::
Computes the maximum of a and b, producing an atom.
a is an atom.
b is an atom.
~zod/try=> (max 10 100)
100
~zod/try=> (max 10.443 9)
10.443
~zod/try=> (max 0 1)
1
++min
Minimum
++ min :: minimum
~/ %min
|= [a=@ b=@]
^- @
?: (lth a b) a
b
::
Computes the minimum of a and b, producing an atom.
a is an atom.
b is an atom.
~zod/try=> (min 10 100)
10
~zod/try=> (min 10.443 9)
9
~zod/try=> (min 0 1)
0
++mod
Modulus
++ mod :: remainder
~/ %mod
|= [a=@ b=@]
^- @
?< =(0 b)
(sub a (mul b (div a b)))
::
Computes the remainder of dividing a by b, producing an atom.
a is an atom.
b is an atom.
++mul
Multiply
++ mul :: multiply
~/ %mul
|= [a=@ b=@]
^- @
=+ c=0
|-
?: =(0 a) c
$(a (dec a), c (add b c))
::
Multiplies a by b, producing an atom.
a is an atom.
b is an atom.
~zod/try=> (mul 3 4)
12
~zod/try=> (mul 0 1)
0
++peg
Axis within axis
++ peg :: tree connect
~/ %peg
|= [a=@ b=@]
^- @
?- b
1 a
2 (mul a 2)
3 +((mul a 2))
* (add (mod b 2) (mul $(b (div b 2)) 2))
==
::
Computes the axis of b within axis a, producing an atom.
a is an atom.
b is an atom.
~zod/try=> (peg 4 1)
4
~zod/try=> (peg 4 2)
8
~zod/try=> (peg 8 45)
269
++sub
Subtract
++ sub :: subtract
~/ %sub
|= [a=@ b=@]
~| %subtract-underflow
^- @
?: =(0 b) a
$(a (dec a), b (dec b))
Subtracts b from a, producing an atom.
a is an atom.
b is an atom.
~zod/try=> (sub 10 5)
5
~zod/try=> (sub 243 44)
199
~zod/try=> (sub 5 0)
5
~zod/try=> (sub 0 5)
! subtract-underflow
! exit