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Class abstract_variables_map

boost::program_options::abstract_variables_map —

Synopsis

class abstract_variables_map {
public:
// construct/copy/destruct
abstract_variables_map();
abstract_variables_map(const abstract_variables_map *);
~abstract_variables_map();

// public member functions
const variable_value & operator[](const std::string &) const;
void next(abstract_variables_map *) ;

// private member functions
virtual const variable_value & get(const std::string &) const;
};

Description

Implements string->string mapping with convenient value casting facilities.

abstract_variables_map construct/copy/destruct

  1. abstract_variables_map();
  2. abstract_variables_map(const abstract_variables_map * next);
  3. ~abstract_variables_map();

abstract_variables_map public member functions

  1. const variable_value & operator[](const std::string & name) const;

    Obtains the value of variable 'name', from *this and possibly from the chain of variable maps.

    • if there's no value in *this.

      • if there's next variable map, returns value from it

      • otherwise, returns empty value

    • if there's defaulted value

      • if there's next varaible map, which has a non-defauled value, return that

      • otherwise, return value from *this

    • if there's a non-defauled value, returns it.

  2. void next(abstract_variables_map * next) ;

    Sets next variable map, which will be used to find variables not found in *this.

abstract_variables_map private member functions

  1. virtual const variable_value & get(const std::string & name) const;

    Returns value of variable 'name' stored in *this, or empty value otherwise.

Copyright 2002-2004 Vladimir Prus

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