ANSI C is a standardized version of the C programming language that was introduced in 1989 by the American National Standards Institute (ANSI). The ANSI C standard defines the syntax and semantics of the C language, including its grammar. In this post, we will explore the ANSI C grammar in more detail.
The ANSI C Grammar
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The ANSI C grammar is defined in the ANSI C standard document, which is available for purchase on the ANSI website. The grammar is specified using a variant of Backus-Naur Form (BNF), which is a notation for defining formal grammars.
The ANSI C grammar consists of a set of production rules, each of which defines a non-terminal symbol in the grammar. The non-terminal symbols represent syntactic categories, such as expressions, statements, and declarations. The production rules specify how the non-terminal symbols can be derived from other non-terminal symbols and terminal symbols, which represent the basic elements of the language, such as identifiers, operators, and literals.
Here’s an example of a production rule from the ANSI C grammar:
declaration: declaration_specifiers init_declarator_list_opt ;
This production rule defines the syntax for a declaration in ANSI C. The declaration_specifiers non-terminal symbol represents the set of type specifiers and storage class specifiers that can appear in a declaration, and the init_declarator_list non-terminal symbol represents a list of declarators that can appear in a declaration. The opt suffix indicates that the init_declarator_list is optional. The ; terminal symbol indicates the end of the declaration.
The ANSI C grammar includes production rules for many syntactic categories, including expressions, statements, declarations, and function definitions. The grammar is detailed and complex, but it provides a precise specification of the syntax and semantics of the C language.
Using the ANSI C Grammar
The ANSI C grammar is a useful tool for understanding the syntax and semantics of the C language. It can be used to analyze and generate C code, to develop compilers and interpreters for the C language, and to write software that analyzes or transforms C code.
There are many tools and libraries available that can parse and analyze C code using the ANSI C grammar. Examples include the GNU Compiler Collection (GCC), the Clang compiler, and the ANTLR parser generator. These tools can be used to analyze and transform C code, to generate code from high-level specifications, or to develop new programming languages that are based on the C syntax.
An ANSI C Grammar in Yacc
The ANSI C grammar in Yacc: http://www.quut.com/c/ANSI-C-grammar-y.html#compound-statement