Reuse of ASF+SDF Specifications by Means of Renaming

                       Merijn de Jonge

Reuse shortens the  time  to  develop  software  systems  and  it
promotes  standardization.  Often,  it  is  difficult  to extract
elements from one project that can be easily used in an unrelated
project   because  of  dependencies  between  portions  of  code.
Decreasing  the  dependencies  between  components  is  therefore
considered  a  good  design  principle for the promotion of reuse
[TS92]. In [ste81] relations between components are described  in
terms   of  coupling  and  cohesion.  These  terms  describe  the
relationships between components and the relationships  within  a
component  respectively.  In  order to promote reuse, a component
should be designed as orthogonal as possible [TS92]  by  lowering
the   coupling   between  modules  and  increasing  the  internal
cohesion.

Several  techniques  exist  for  the  development   of   reusable
orthogonal  components.  Examples  are  higher-order  programming
techniques  in  functional   languages,  inheritance  in  object-
oriented  languages and import and parameterization mechanisms in
modular languages.  This thesis will concentrate on reuse in  the
algebraic  specification  formalism  ASF+SDF.  Because  it  is  a
modular  formalism,   we   will   concentrate   on   import   and
parameterization  as  techniques  for  the  design  and reuse  of
orthogonal modules.