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YACC

• YACC stands for Yet Another Compiler Compiler.
• YACC provides a tool to produce a parser for a given grammar.
• YACC is a program designed to compile a LALR (1) grammar.
• It is used to produce the source code of the syntactic analyzer of the language produced by LALR (1) grammar.
• The input of YACC is the rule or grammar and the output is a C program.

These are some points about YACC:

Input: A CFG- file.y

Output: A parser y.tab.c (yacc)

• The output file “file.output” contains the parsing tables.
• The file “file.tab.h” contains declarations.
• The parser called the yyparse ().
• Parser expects to use a function called yylex () to get tokens.

The basic operational sequence is as follows:

This file contains the desired grammar in YACC format.

It shows the YACC program.

It is the c source program created by YACC.

C Compiler

Executable file that will parse grammar given in gram.Y