LibCppCmdLine: C++ Command Line Parsing Library

Current Release

Version

1.0 Beta 15

Introduction

LibCppCmdLine is a modern, lightweight, and cross-platform C++ command line parsing library. It provides a series of classes for parsing command line arguments passed to a program via the main function and populating command line parameters with values as a result of parsing. A program that uses this library will:

1. Define and create command line parameters.
2. Create a new command line parser.
3. Add the command line parameters to the parser.
4. Parse the command line arguments with the parser.
5. Examine the parameters that were populated by the parser.

The library uses the C++ Standard Template Library (STL) and thus has no major external dependencies (see note below). It is lightweight enough that it is designed to be added directly to a program's code base. However, the program can still be precompiled and statically or dynamically linked if desired. This library also uses exceptions, but only for enforcing class invariants to prevent programming errors; the library will only generate exceptions if the programmer defines parameters wrong or adds duplicate parameters, thus no try / catch blocks are necessary for final code.

Note

The tests for this library do have an external dependency: GoogleTest. However, the tests are only needed for testing changes to the library code itself and are not needed for a program that will simply include the library as-is.

Features

• Lightweight.
• Cross-platform.
• No external dependencies.
• Designed to be added and compiled straight into your program's code base.
• Supports two types of options and two types of positional parameters.
• Options can have either the Windows or Unix style prefix.
• Standard options act like simple switches.
• Value options suport multiple values and their own option parameters.
• Positional parameters come in single or multi-value varieties.
• The parser can generate usage and help info based on the parameters.

Limitations

• Only supports ASCII command line arguments.
• Not designed for programs with a highly complex command line use case.

Namespaces

Everything in this library is contained within the CmdLine namespace.

Key Classes

The following classes are necessary to parse command line arguments.

Class (* base)	Purpose
CmdLine::Parser	Parses command line arguments
CmdLine::Param *	A variable that stores data from the command line
CmdLine::ArgParam *	A CmdLine::Param populated by CommandLine arguments
CmdLine::ProgParam	A CmdLine::ArgParam populated by the program name argument
CmdLine::Option	A CmdLine::ArgParam that represents an option
CmdLine::ValueOption	A CmdLine::Option populated with values
CmdLine::OptionParam	Provides parameters for CmdLine::ValueOption values
CmdLine::PosParam	A Positional CmdLine::ArgParam
CmdLine::MultiPos	A multi-value positional CmdLine::ArgParam

Key Structs

The following structs are necessary to define command line parameters.

Struct	Purpose
CmdLine::ProgParam::Definition	Used to construct a CmdLine::ProgParam
CmdLine::Option::Definition	Used to construct a CmdLine::Option
CmdLine::ValueOption::Definition	Used to construct a CmdLine::ValueOption
CmdLine::OptionParam::Definition	Used to construct a CmdLine::OptionParam
CmdLine::PosParam::Definition	Used to construct a CmdLine::PosParam
CmdLine::MultiPosParam::Definition	Used to construct a CmdLine::MultiPosParam

Todo

Add example section

Todo

Add information about adding to your codebase