Compiler-compiler

In computer science, a compiler-compiler or compiler generator is a programming tool that creates a parser, interpreter, or compiler from some form of formal description of a programming language and machine. The input may be a text file containing the grammar written in BNF or EBNF that defines the syntax of a programming language, and whose generated output is some source code of the parser for the programming language, although other definitions exist. Usually, the resulting source code will have to be extended upon before a complete compiler emerges.Metacompilers reduce the task of writing compilers by automating the aspects that are the same regardless of the object language. This makes possible the design of domain-specific languages which are appropriate to the specification of a particular problem. A metacompiler reduces the cost of producing translators for such domain-specific object languages to a point where it becomes economically feasible to include in the solution of a problem a domain-specific language design. In computer science, a compiler-compiler or compiler generator is a programming tool that creates a parser, interpreter, or compiler from some form of formal description of a programming language and machine. The input may be a text file containing the grammar written in BNF or EBNF that defines the syntax of a programming language, and whose generated output is some source code of the parser for the programming language, although other definitions exist. Usually, the resulting source code will have to be extended upon before a complete compiler emerges. A metacompiler is a software development tool used chiefly in the construction of compilers, translators, and interpreters for other programming languages. The input to a metacompiler is a computer program written in a specialized programming metalanguage designed chiefly for the purpose of constructing compilers. The language of the compiler produced is called the object language. The minimal input producing a compiler is a metaprogram specifying the object language grammar and semantic transformations into an object program. A typical parser generator associates executable code with each of the rules of the grammar that should be executed when these rules are applied by the parser. These pieces of code are sometimes referred to as semantic action routines since they define the semantics of the syntactic structure that is analyzed by the parser. Depending upon the type of parser that should be generated, these routines may construct a parse tree (or abstract syntax tree), or generate executable code directly. One of the earliest (1964), surprisingly powerful, versions of compiler-compilers is META II, which accepted an analytical grammar with output facilities that produce stack machine code, and is able to compile itself and other languages. Some experimental compiler-compilers take as input a formal description of programming language semantics, typically using denotational semantics. This approach is often called 'semantics-based compiling', and was pioneered by Peter Mosses' Semantic Implementation System (SIS) in 1978. However, both the generated compiler and the code it produced were inefficient in time and space. No production compilers are currently built in this way, but research continues. The Production Quality Compiler-Compiler project at Carnegie-Mellon University does not formalize semantics, but does have a semi-formal framework for machine description. Compiler-compilers exist in many flavors, including bottom-up rewrite machine generators (see JBurg) used to tile syntax trees according to a rewrite grammar for code generation, and attribute grammar parser generators (e.g. ANTLR can be used for simultaneous type checking, constant propagation, and more during the parsing stage). A metacompiler's metalanguage is a powerful string and symbol processing languages that are also useful for generating a wide range of other software engineering and analysis tools. Besides being useful for domain-specific language development, a metacompiler is itself a prime example of a domain-specific language, designed for the domain of compiler writing.