Registering and Opts

Registering and opts parsing. More...

Functions
bool	tgen::has_opt (std::size_t index)
	Checks if opt at some index exists.
bool	tgen::has_opt (const std::string &key)
	Checks if opt with with some key exists.
template<typename T>
T	tgen::opt (size_t index, std::optional< T > default_value=std::nullopt)
	Gets opt by key.
template<typename T>
T	tgen::opt (const std::string &key, std::optional< T > default_value=std::nullopt)
	Gets opt by key.
void	tgen::register_gen (int argc, char **argv)
	Sets up the generator.
void	tgen::register_gen (std::optional< long long > seed=std::nullopt)
	Sets up the generator without arguments.
void	tgen::set_cpp_version (int version)
	Sets C++ version.

Detailed Description

Registering and opts parsing.

Registering

The first line of your generator should be:

#include "tgen.h"
 
int main(int argc, char** argv) {
    tgen::register_gen(argc, argv);
    
    // Rest of the generator.
}

This does two things:

1. Sets up the seed for random generator based on the arguments (excluding the executable name). That is, ./a.out -n 10 and ./b.out -n 10 will use the same seed.
2. Parses the opts (given in the arguments).

Opts

Opts are a list of either named or positional options.

Named options is given in one of the following formats:

1. -keyname=value or –keyname=value (ex. -n=10, –test-count=20)
2. -keyname value or –keyname value (ex. -n 10, –test-count 20)

Positional options are numbered from 0 sequentially.

For example, if you compile your code to a.out, calling ./a.out -n 10 str –q=5 -1.1e2 results in the following opts:

• Named
  • n: 10
  • q: 5
• Positional
  • 0: str
  • 1: -110

Consuming opts

You can consume the opts by using opt<>:

int n = tgen::opt<int>("n");
std::string s = tgen::opt<std::string>(0, ""); // Default value, if opt is not found.

Function Documentation

has_opt() [1/2]

bool tgen::has_opt ( const std::string & key )

inline

Checks if opt with with some key exists.

Parameters

key	Key of named opt.

Returns

If there is named opt with key.

Examples

// Checks if there is an opt with "q".
if (tgen::has_opt("q")) std::cout << "q found!" << std::endl;

Definition at line 1113 of file tgen.h.

has_opt() [2/2]

bool tgen::has_opt ( std::size_t index )

inline

Checks if opt at some index exists.

Parameters

index

Index of positional opt.

Returns

If there is positional opt at index.

Examples

// Checks if there is an opt at 0.
if (tgen::has_opt(0)) std::cout << "opt found!" << std::endl;

Definition at line 1107 of file tgen.h.

opt() [1/2]

template<typename T>

T tgen::opt	(	const std::string &	key,
		std::optional< T >	default_value = std::nullopt )

Gets opt by key.

Template Parameters

T	Type of the opt.

Parameters

key	Key to fetch.
default_value	Default value to be returned, if key is not found.

Returns

The value of opt with key. If not found, returns default_value.

Exceptions

std::runtime_error

if opt is not found and default_value is not given.

Examples

// Consumes opt with "q".
int q = tgen::opt<int>("q");

Definition at line 1139 of file tgen.h.

opt() [2/2]

template<typename T>

T tgen::opt	(	size_t	index,
		std::optional< T >	default_value = std::nullopt )

Gets opt by key.

Template Parameters

T	Type of the opt.

Parameters

index	index to fetch.
default_value	Default value to be returned, if index is not found.

Returns

The value of opt at index. If not found, returns default_value.

Exceptions

std::runtime_error

if opt is not found and default_value is not given.

Examples

// Consumes opt at 0.
int q = tgen::opt<int>(0);

Definition at line 1125 of file tgen.h.

register_gen() [1/2]

void tgen::register_gen ( int argc, char ** argv )

inline

Sets up the generator.

Parameters

argc	Argument count, from the main function.
argv	Argument vector, from the main function.

Sets up the opts, and the seed of the random number generator. The seed is dependent on the arguments (excluding the executable name).

Examples

#include "tgen.h"
 
int main(int argc, char** argv) {
    // Register generator.
    tgen::register_gen(argc, argv);
}

Definition at line 1155 of file tgen.h.

register_gen() [2/2]

void tgen::register_gen ( std::optional< long long > seed = std::nullopt )

inline

Sets up the generator without arguments.

Parameters

seed	Seed for the random number generator.

Examples

#include "tgen.h"
 
int main() {
    // Register generator with seed 42.
    tgen::register_gen(42);
}

Or even:

#include "tgen.h"
 
int main() {
    // Register generator with default seed.
    tgen::register_gen();
}

Definition at line 1166 of file tgen.h.

set_cpp_version()

void tgen::set_cpp_version ( int version )

inline

Sets C++ version.

Parameters

version

The C++ version (17, 20, or 23).

This can be used by some functions to find counter testcases for specific systems.

Examples

// Sets as C++17.
tgen::set_cpp_version(17);

This can also be set by command argument:

• ./executable tgen::CPP:20: equivalent to tgen::set_cpp_version(20).

Definition at line 903 of file tgen.h.