The Spirit Parser Framework is an

object oriented Object-oriented programming (OOP) is a programming paradigm based on the concept of '' objects''. Objects can contain data (called fields, attributes or properties) and have actions they can perform (called procedures or methods and impleme ...

recursive descent In computer science, a recursive descent parser is a kind of top-down parser built from a set of mutually recursive procedures (or a non-recursive equivalent) where each such procedure implements one of the nonterminals of the grammar. Thus t ...

parser generator 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 most common type of compiler- ...

framework implemented using template

metaprogramming Metaprogramming is a computer programming technique in which computer programs have the ability to treat other programs as their data. It means that a program can be designed to read, generate, analyse, or transform other programs, and even modi ...

techniques. Expression templates allow users to approximate the syntax of

extended Backus–Naur form Extension, extend or extended may refer to: Mathematics Logic or set theory * Axiom of extensionality * Extensible cardinal * Extension (model theory) * Extension (proof theory) * Extension (predicate logic), the set of tuples of values ...

(EBNF) completely in C++. Parser objects are composed through

operator overloading In computer programming, operator overloading, sometimes termed ''operator ad hoc polymorphism'', is a specific case of polymorphism, where different operators have different implementations depending on their arguments. Operator overloading ...

and the result is a backtracking LL(∞) parser that is capable of parsing rather

ambiguous Ambiguity is the type of meaning in which a phrase, statement, or resolution is not explicitly defined, making for several interpretations; others describe it as a concept or statement that has no real reference. A common aspect of ambiguit ...

grammars. Spirit can be used for both

lexing Lexical tokenization is conversion of a text into (semantically or syntactically) meaningful ''lexical tokens'' belonging to categories defined by a "lexer" program. In case of a natural language, those categories include nouns, verbs, adjectives ...

and parsing, together or separately. This framework is part of the Boost libraries.

Operators

Because of limitations of the C++ language, the syntax of Spirit has been designed around the operator precedences of C++, while bearing resemblance to both EBNF and

regular expressions A regular expression (shortened as regex or regexp), sometimes referred to as rational expression, is a sequence of character (computing), characters that specifies a pattern matching, match pattern in string (computer science), text. Usually ...

Example

This example shows how to use an inline parser expression with a semantic action. #include #include #include #include int main()

References

External links

Spirit parser framework github pageSpirit parser frameworkArticle on Spirit by designer Joel de Guzman in Dr. Dobb's Journal
Parser generators {{programming-software-stub