:title
Append a child

:sig
function push(value : dval, child : as dval) dval

:params
value : target value
child : value to append

:returns
The changed target value.

:content
`push(value, child)` appends `child` with the next numeric key. It changes and returns `value`.

:example capy render
var list := dval([])
list = push(list, "Ada")
print(list[0], "\n")

:see-group
dval-access
