OmniSketch::Util::ConfigParser Class Reference

Parse config file and return its configurations in a versatile manner. More...

#include <utils.h>

Public Member Functions
	ConfigParser (const std::string_view config_file)
	Open the config file. More...
bool	succeed () const
	Return whether the parsing succeeds. More...
void	setWorkingNode (const std::string_view path="")
	Set the working node in the config file. More...
template<typename T >
bool	parseConfig (T &arg, const std::string_view arg_name, const bool error_logging=true) const
	Get the configuration and store it directly into the object. More...

Detailed Description

Parse config file and return its configurations in a versatile manner.

Author

dromniscience (you@d.nosp@m.omai.nosp@m.n.com)

Constructor & Destructor Documentation

ConfigParser()

OmniSketch::Util::ConfigParser::ConfigParser

(

const std::string_view

config_file

)

Open the config file.

Parameters

config_file

path to the config file

Member Function Documentation

parseConfig()

template<typename T >

bool OmniSketch::Util::ConfigParser::parseConfig ( T &  arg, const std::string_view  arg_name, const bool  error_logging = true  ) const

inline

Get the configuration and store it directly into the object.

Template Parameters

T	supported types: int32_t size_t double bool std::string std::vector<int32_t> std::vector<size_t> std::vector<double> std::vector<std::string> toml::array

Parameters

arg	the object to be written to
arg_name	the name in config file
error_logging	Enable / disable error logging when parsing fails (by default enabled)

Returns

true on success; false otherwise. Possible reasons for a false return:

• Misspell the key name in config file.
• Working node unset or is wrong.

Attention

On failure, the object may be in an inconsistent state, particularly when arg is a vector or an toml::array, and an error be logged. To disable error logging, which might be particularly useful when the config is meant to be optional, set logging_error to false.

setWorkingNode()

void OmniSketch::Util::ConfigParser::setWorkingNode

(

const std::string_view

path = ""

)

Set the working node in the config file.

The data about to read should always locate in the working node. See example below for a better understanding. An argument of "" (or void) means the root. This method can be invoked upon a single instances multiple times.

Parameters

path	path to the working node

Example

Suppose the toml file is

# toml.toml
 
key = 2 # then this!
 
[A.B.C]
key = 1 # first parse this!

and you want to fetch the value for key. This code snippet works for you.

# example.cpp
using namespace OmniSketch::Util;
 
// open file and parse
auto parser = ConfigParser("toml.toml");
// check whether the parsing succeed
if(!parser.succeed()) exit(-1);
 
// set working node to [A.B.C]
parser.setWorkingNode("A.B.C");
 
int first_key;
parser.parseConfig(first_key, "key");
 
// reset working node to the root
parser.setWorkingNode();
// Equivalently, parser.setWorkingNode("");
 
int second_key;
parser.parseConfig(second_key, "key");

succeed()

bool OmniSketch::Util::ConfigParser::succeed

(

)

const

Return whether the parsing succeeds.