t=: 1 2 3
   t
1 2 3
   names noun
t     
   t
1 2 3
   names locale
base
j   
z   
   names_base_ noun
t
   t_abc_ =: 'hi there'
   t
1 2 3
   t_abc_
hi there
   names locale
abc 
base
j   
z   
   names_abc_ noun
t
   make
0!:0@<
   make_abc_
0!:0@<
   names_abc_ verb

   make_z_
0!:0@<
   invalid_method_name_indicator =: 'unknown'
   for_effect_only =: monad def '''unspecified'''
   invalid_method_name_indicator
unknown
   for_effect_only''
unspecified
   system'cat simple.object.ijs'
NB. A simple object having a data value
NB. and methods to access and set the data value.

data =: 0

simple =: monad define
('method' ; 'value') =. 2 take y.
if. method match 'type'
    do. 'simple object'
  elseif. method match 'get'
    do. data
  elseif. method match 'set'
    do. for_effect_only data =: value
  elseif. 1
    do. root_object method ; value
end.
)

   make_foo_'simple.object.ijs'
   names_foo_ noun
data 
   names_foo_ verb
simple 
   simple_foo_ <'type'
simple object
   simple_foo_ <'get'
0
   simple_foo_ 'set'; 'hi there'
unspecified
   simple_foo_ 'get'
hi there
   cat'root.object.ijs'
NB. The root object
NB. This object has no data structure and
NB. implements only the type method.

root_object_z_ =. monad define
('method' ; 'value') =. 2 take y.
if. method -: 'type'
  do. 'root object'
  else. 'In root object: ',method,': Invalid method name.'
end.
)

   simple_foo_ <'bar'
In root object: bar: Invalid method name.
   make_a_'stack.object.ijs'
   stack_a_ <'emptyp'
1