anchor.diff:  identifier-syntax,2
   identifier?,2
   ieee-environment,2
  -if,2
  +if,4
   imag-part,2
   implementation-restriction-violation?,2
   implicit-exports,2
  
positive.code: library-object-filename,2
  library-requirements,2
  library-version,2
  list,2
  list*,2
  list->fxvector,2
  list->string,2
  
negative.code: acquire-lock,2
  add1,2
  alias,2
  and,5
  andmap,2
  angle,2
  annotation-expression,2
  