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Show 90 b.1 Generating . Parser n-tuple of a relational database. Along with the struQture, it The MINI compiler writing system l77] was employed in generating the SICUDL parser. It supports a BNF-like notation for languages and produces a recursive descent parser. Because the parser mirrors the BNF language description, changes to the language are not likely to require an extensive rewrite of ad-hoc code. MINI allows a language to evolve over a period of time with little effort required to alter the parser. 6.2 DEFSTRUCT: Generating ASSASSIN Data Structures DEFSTRUCT, as was stated above, is used to generated all the data structures required for simulating and compiling SICUDL. It allows for uniform generation of data accessors and alteration of data structures with no changes to existing code referencing unaltered portions of those data structures. DEFSTRUCTs are used to generate the state database, the transition database, and the databases used in. maintaining information about the placement' of column connections and breaks in the compiler. DEFSTRUCT defines a structure much like the generates a set of standard constructors, alterants and accessors for the data structure such that the addition of fields in the structure does not require any code changes for using the accessors and -\lterants. !-,.,o changes flere required to the state and transition databases as the system development progressed. These were the addition of the |
