attr_reader, attr_writer and attr_accessor in J

attr.ijs

coclass 'attr'

attr_reader =: monad define
  loc =. > coname ''
  names =. ;: y
  dup =. ((# names) & $) & <
  fullnames =. names ,. dup ('_' , loc , '_')
  ". joinstring"1 (dup 'get_') ,. fullnames ,. (dup '=: 3 : ''') ,. names ,. (dup '''')
)

attr_writer =: monad define
  loc =. > coname ''
  names =. ;: y
  dup =. ((# names) & $) & <
  fullnames =. names ,. dup ('_' , loc , '_')
  ". joinstring"1 (dup 'set_') ,. fullnames ,. (dup '=: 3 : ''') ,. names ,. (dup '=: y''')
)

attr_accessor =: monad define
  attr_reader y
  attr_writer y
)