About this Document
Chapter 1	Language Concepts	5
Chapter 2	Identifiers	19
Chapter 3	Conditions	25
Chapter 4	Time Expressions	37
Chapter 5	Rules	61
Chapter 6	Message and Command Queues	71
Chapter 7	Listeners	75
Chapter 8	Commands	81
Chapter 9	Special Symbol Commands	125
Chapter 10	Source File Directives	133
Chapter 11	Symbolic Substitution	138
Appendix A.	Special Symbols	147
Appendix B.	Transitional Features	151
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