The compiler compiler

Publisher Summary This chapter presents detailed specification of a system for describing the form and meaning of the statements in a phrase structure language, for example, a scientific autocode. Given such a description, the compiler compiler will generate a compiler for the language, that is, a program that can read and translate another program written in that language. This system may be considered to operate in two phases. In the primary phase, it accepts and records the definition of a phrase structure language, and in the secondary phase it will translate a source program written in that language. The two phases are not completely separate and further definitions can be given in the middle of a source program. Their influence only extends forward and not back to the material already processed. The primary material consists mainly of format definitions and phrase definitions that describe the form of statements and their constituent expressions, and format routines that describe their meaning. The meaning of a new format is defined in terms of existing formats, which may be either built-in or previously defined ones. Five kinds of statements comprise the basic primary language and they are recognized by the following headings or master phrases: PHRASE, FORMAT CLASS, FORMAT, IGNORE, and ROUTINE.