Contents

• 1 Introduction
• 2 Rational
  • 2.1 The Computer Languages Factory
  • 2.2 Abstract Syntax
  • 2.3 Isolating Abstract Syntax from Concrete Syntax
  • 2.4 Modularity
  • 2.5 Second-Order Abstract Syntax
• 3 Tutorial
  • 3.1 Starting with an Example
  • 3.2 Expressions
  • 3.3 Statements
  • 3.4 Lists
  • 3.5 Binders
  • 3.6 Formalism Inclusion
  • 3.7 Formalism Extension
• 4 User's Manual
  • 4.1 Files Naming Convention
  • 4.2 The AS Centaur-Environment
    • 4.2.1 Compiling a New Specification
    • 4.2.2 Getting Help in Case of Errors or Warnings
    • 4.2.3 Using an AS-defined Formalism in the Centaur Environment
    • 4.2.4 Modifying a Specification
• 5 Reference Manual
  • 5.1 Lexical Elements
    • 5.1.1 Keywords
    • 5.1.2 Identifiers
    • 5.1.3 Comments
    • 5.1.4 Empty Lines
  • 5.2 Names
  • 5.3 Typed Names
  • 5.4 Definition of Operators
    • 5.4.1 Atomic Operators
    • 5.4.2 Fixed Arity Operators
    • 5.4.3 List Operators
    • 5.4.4 Second-order Operators
    • 5.4.5 Modularity
    • 5.4.6 Syntax
  • 5.5 Definition of Phyla
    • 5.5.1 Type Inclusion
    • 5.5.2 Union of Phyla
    • 5.5.3 Modularity
    • 5.5.4 Syntax
  • 5.6 Predefined Types
  • 5.7 Complete Definition of an Abstract Syntax
  • 5.8 Extension of a Formalism
  • 5.9 Effectiveness
  • 5.10 The Complete Concrete Syntax of AS
  • 5.11 The Complete Abstract Syntax of AS
• 6 Errors and Warnings
  • 6.1 Type-Checker Errors and Warnings
    • 6.1.1 ``The name X is already used for Y.''
    • 6.1.2 ``The type X is not defined.''
    • 6.1.3 ``I cannot find the formalism X.''
    • 6.1.4 ``The formalism X does not define Y.''
    • 6.1.5 ``The phylum X is closed.''
    • 6.1.6 ``The phylum X should be a singleton to be used in a lambda definition.''
    • 6.1.7 ``The phylum X (= Y) should be a singleton to be used in a lambda definition.''
    • 6.1.8 ``In phylum X, Y should be defined with signature Z to be usable in a lambda definition.''
    • 6.1.9 ``The phylum X is not effective.''
    • 6.1.10 ``The name meta is not allowed for an operator.''
    • 6.1.11 ``The name X is both defined as Y and imported from Z.''
    • 6.1.12 ``The two phyla X and Y are identical (=Z).''
    • 6.1.13 ``The formalism X is not defined using as.''
    • 6.1.14 ``The file X defining Y cannot be read.''
    • 6.1.15 ``You can't define and extend X at the same time.''
  • 6.2 Messages from the AS Centaur-Environment
    • 6.2.1 ``The source file has been modified but not saved.''
    • 6.2.2 ``Your definition is not yet type-checked.''
    • 6.2.3 ``The name of the file (X) differs from the name of the language defined (Y).''
    • 6.2.4 ``X written.''
• 7 Implementation Notes
  • 7.1 Lacks, Bugs and Features
  • 7.2 Type-Checking
  • 7.3 Lisp Code Generation
  • 7.4 Prolog Code Generation
  • 7.5 Files Generation
• References
• Index
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