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Belina, Hogrefe (edits Reed)

7. Shorthands

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A shorthand construct is a standard extension to the primitive constructs of the language kernel, and is defined in terms of other constructs (ultimately by the primitive constructs) of the language. As indicated by the name, a shorthand simplifies the use of the language and reduces the si; e of a system description, since a collection of primitive constructs can be represented by one construct.

Before a system description can be interpreted, all shorthands must be expanded (transformed to primitive constructs), since the interpretation rules apply only to the language kernel (see 'Overview of SDL Concpet'). The transformation of shorthands cannot be made in an arbitrarily order, because this would result in ambiguity in some cases. The prescribed order of transformation is as follows

  1. macro
  2. options
  3. asterisk state
  4. state list
  5. multiple appearance of state
  6. asterisk input
  7. asterisk save
  8. stimulus list
  9. output list
  10. implicit transition
  11. dash nexstate
  12. service
  13. continuous signal
  14. enabling condition
  15. imported and exported value

Note that in addition to the above list, there are also other minor shorthands. The description of some of the shorthands is given below, for the other shorthands the reader is referred to [l].

Asterisk state
Implicit transition
Dash nextstate
Imported and exported value

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