NoManip

The GetOpt_pp class can be additionally queried with two other ways, for people who doesn't like manipulators:

• using the getopt() method
• using iterators

Please note that the 'spirit' of GetOpt_pp is to be used as a stream, therefore to be used with manipulators.

The getopt() method

The options can be retrieved by invoking the getopt() method. This method receives the same parameters as the Option manipulators, except that the result is returned rather than passed as a parameter.

     cout << ops.getopt<int>('i');

The getopt() method can receive a default value, to be returned when the option is not found.

When exceptions are not enabled, the returned value is undefined if an error occurred (i.e. invalid format, option not found, parsing error, etc.).

Using iterators

You can iterate over all the command line options. There are two iterators:

• short_iterator: iterates over the short format options
• long_iterator: iterates over the long format options

Both iterators implement the following interface:

• pre-increment operator: moves to the next command line entry
• the option() method: returns current option; a char for short_iterator, a std::string for a long_iterator
• the args() method: returns a std::vector<std::string> const reference containing all the options for the current command line entry.

Iterators are used as any STL iterator: you obtain the first using the GetOpt_pp::begin() method, increment, and compare against the GetOpt_pp::end() method.

The following example iterates over all the long format options, showing each one and the number of arguments per option:

int main(int argc, char* argv[])
{
	GetOpt_pp ops(argc, argv);

	for(GetOpt_pp::long_iterator it = ops.begin(); it != ops.end(); ++it)
		std::cout << "\t" << it.option() << " has " << it.args().size() << " arguments." << std::endl;
}

//

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