argparse/README.md
Pranav Srinivas Kumar 9e1c0bbc2f
Update README.md
2019-03-31 11:15:05 -04:00

127 lines
3.2 KiB
Markdown

# Argument Parser
## Highlights
* Simply include <argparse.hpp>
* Requires C++17
* MIT License
## Positional Arguments
```cpp
argparse::ArgumentParser program("main");
program.add_argument("input");
program.add_argument("output");
program.parse_args({"./main", "rocket.msh", "thrust_profile.csv"});
std::string input = program.get("input"); // "rocket.msh"
std::string output = program.get("output"); // "thrust_profile.csv"
```
## Optional Arguments
```cpp
argparse::ArgumentParser program("main");
program.add_argument("--config")
.help("configuration file")
.default_value(std::string("config.json"));
program.add_argument("-n", "--num_iterations")
.help("The list of input files")
.action([](const std::string& value) { return std::stoi(value); });
program.parse_args({"./main", "-n", "36"});
std::string config = program.get("--config"); // "config.json"
int num_iterations = program.get<int>("-n"); // 36
```
## Vector of Arguments
```cpp
argparse::ArgumentParser program("main");
program.add_argument("--input_files")
.help("The list of input files")
.nargs(3);
program.parse_args({"./main", "--input_files", "config.yml", "System.xml"});
auto files = program.get<std::vector<std::string>>("--input_files"); // {"config.yml", "System.xml"}
```
## Toggle Arguments
```cpp
argparse::ArgumentParser program("test");
program.add_argument("--verbose", "-v")
.default_value(false)
.implicit_value(true);
program.parse_args({ "./main", "--verbose" });
auto a = program.get<bool>("--verbose"); // true
```
## Compound Arguments
```cpp
argparse::ArgumentParser program("test");
program.add_argument("-a")
.default_value(false)
.implicit_value(true);
program.add_argument("-b")
.default_value(false)
.implicit_value(true);
program.add_argument("-c")
.nargs(2)
.action([](const std::string& value) { return std::stof(value); });
program.parse_args({ "./main", "-abc", "3.14", "2.718" });
auto a = program.get<bool>("-a"); // true
auto b = program.get<bool>("-b"); // true
auto c = program.get<std::vector<float>>("-c"); // {3.14f, 2.718f}
```
## Positional Arguments with Compound Toggle Arguments
```cpp
argparse::ArgumentParser program("test");
program.add_argument("numbers")
.nargs(3)
.action([](const std::string& value) { return std::stoi(value); });
program.add_argument("-a")
.default_value(false)
.implicit_value(true);
program.add_argument("-b")
.default_value(false)
.implicit_value(true);
program.add_argument("-c")
.nargs(2)
.action([](const std::string& value) { return std::stof(value); });
program.add_argument("--files")
.nargs(3);
program.parse_args({ "./test.exe", "1", "-abc", "3.14", "2.718", "2", "--files",
"a.txt", "b.txt", "c.txt", "3" });
auto numbers = program.get<std::vector<int>>("numbers"); // {1, 2, 3}
auto a = program.get<bool>("-a"); // true
auto b = program.get<bool>("-b"); // true
auto c = program.get<std::vector<float>>("-c"); // {3.14f, 2.718f}
auto files = program.get<std::vector<std::string>>("--files"); // {"a.txt", "b.txt", "c.txt"}
```