examples/c++/README.md - bison - Git at Google


            
            # Examples in C++


            This directory contains examples of Bison grammar files in C++.


            You can run `make` to compile these examples.  And `make clean` to tidy

            
            afterwards.


            ## simple.yy - Simple example in C++14

            
            A very simple example in C++, based on variants and symbol constructors.

            
            Variants allow to use any C++ type as semantic value type, and symbol

            
            constructors ensure consistency between declared token kind and effective

            
            semantic value.


            Run as `./simple`.


            Extracted from the documentation: [A Simple C++

            
            Example](https://www.gnu.org/software/bison/manual/html_node/A-Simple-C_002b_002b-Example.html).


            ## variant.yy - Self-contained example in C++98

            
            A variation of simple.yy, in C++98.


            Run as `./variant`.


            ## variant-11.yy - Self-contained example in modern C++

            
            Another variation of simple.yy, closely related to the previous one, but

            
            exhibiting support for C++11's move semantics.


            Run as `./variant` or `./variant NUMBER`.


            ## calc++ - A Complete C++ Example

            
            A fully featured C++ version of the canonical example for parsers: a

            
            calculator.  Also uses Flex for the scanner.


            Don't look at this example first: it is fully featured and can serve as a

            
            starting point for a clean parser in C++.  The previous examples are better

            
            introductory examples, and the C examples are also useful introductory

            
            examples.


            Extracted from the documentation: [A Complete C++

            
            Example](https://www.gnu.org/software/bison/manual/html_node/A-Complete-C_002b_002b-Example.html).


            ## glr


            This example demonstrates the use of GLR parsers to handle (local)

            
            ambiguities in the C++ language.  See the node "Merging GLR Parses" in

            
            Bison's documentation.


            It uses (Bison) variants to store objects as semantic values.  It also

            
            demonstrates custom error messages in C++.


            <!---


            Local Variables:

            
            fill-column: 76

            
            ispell-dictionary: "american"

            
            End:


            Copyright (C) 2018-2021 Free Software Foundation, Inc.


            Permission is granted to copy, distribute and/or modify this document

            
            under the terms of the GNU Free Documentation License, Version 1.3 or

            
            any later version published by the Free Software Foundation; with no

            
            Invariant Sections, with no Front-Cover Texts, and with no Back-Cover

            
            Texts.  A copy of the license is included in the "GNU Free

            
            Documentation License" file as part of this distribution.


            LocalWords:  mfcalc calc parsers yy ispell american

            
            --->
	# Examples in C++

	This directory contains examples of Bison grammar files in C++.

	You can run `make` to compile these examples. And `make clean` to tidy
	afterwards.

	## simple.yy - Simple example in C++14
	A very simple example in C++, based on variants and symbol constructors.
	Variants allow to use any C++ type as semantic value type, and symbol
	constructors ensure consistency between declared token kind and effective
	semantic value.

	Run as `./simple`.

	Extracted from the documentation: [A Simple C++
	Example](https://www.gnu.org/software/bison/manual/html_node/A-Simple-C_002b_002b-Example.html).

	## variant.yy - Self-contained example in C++98
	A variation of simple.yy, in C++98.

	Run as `./variant`.

	## variant-11.yy - Self-contained example in modern C++
	Another variation of simple.yy, closely related to the previous one, but
	exhibiting support for C++11's move semantics.

	Run as `./variant` or `./variant NUMBER`.

	## calc++ - A Complete C++ Example
	A fully featured C++ version of the canonical example for parsers: a
	calculator. Also uses Flex for the scanner.

	Don't look at this example first: it is fully featured and can serve as a
	starting point for a clean parser in C++. The previous examples are better
	introductory examples, and the C examples are also useful introductory
	examples.

	Extracted from the documentation: [A Complete C++
	Example](https://www.gnu.org/software/bison/manual/html_node/A-Complete-C_002b_002b-Example.html).

	## glr

	This example demonstrates the use of GLR parsers to handle (local)
	ambiguities in the C++ language. See the node "Merging GLR Parses" in
	Bison's documentation.

	It uses (Bison) variants to store objects as semantic values. It also
	demonstrates custom error messages in C++.

	<!---

	Local Variables:
	fill-column: 76
	ispell-dictionary: "american"
	End:

	Copyright (C) 2018-2021 Free Software Foundation, Inc.

	Permission is granted to copy, distribute and/or modify this document
	under the terms of the GNU Free Documentation License, Version 1.3 or
	any later version published by the Free Software Foundation; with no
	Invariant Sections, with no Front-Cover Texts, and with no Back-Cover
	Texts. A copy of the license is included in the "GNU Free
	Documentation License" file as part of this distribution.

	LocalWords: mfcalc calc parsers yy ispell american
	--->