urbit/pub/doc/hoon/runes/dt/dtls.md

dotlus, .+, %dtls

Increment

.+ is a natural hoon that generates nock operator 4, which increments an atomic operand.

Produces

Twig: [%dtls p=twig]

Sample

p is a twig

Tall form

.+  p

Wide form

.+(p)

Irregular form

+(p)

Examples

~zod/try=> +(6)
7
~zod/try=> +(2)
3

In the most straightforward case .+ increments its operand.

~zod/try=> +(~zod)
1
/~zod/try=> `@`~zod
0
/~zod/try=> `@`'a'
97    
~zod/try=> +('a')
98
/~zod/try=> `@`0xff
255    
~zod/try=> +(0xff)
256
~zod/try=> +(41)
42

When passed a non-atomic odored atoms .+ down-casts to an atom.

~zod/try=> +([1 2])
! type-fail
! exit

Passing an operand that cannot be directly down-cast to an atom produces a type-fail.