The phrase h=: f : g defines h as the function whose monadic case is f and whose dyadic case is g. The components f and g may be functions already defined and named, or they may be tacit or explicit phrases. Moreover, either (but not both) may be defined in terms of the other by using $: for self-reference in a tacit definition.
| v0=: 10&^. : ^. | Base 10 log for monadic case |
| v1=: 10&$: : ^. | Same using self-reference to dyad |
| v2=: 10&^. :($:*^.@(10"0)%^.@[) | Same using self-reference to monad |
| d3=: res=: [: : | | Domain of monad is empty (dyadic only) |
| m4=: abs=: | : [: | Domain of dyad is empty (monadic only) |