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// file : build/config/utility -*- C++ -*-
// copyright : Copyright (c) 2014-2015 Code Synthesis Ltd
// license : MIT; see accompanying LICENSE file
#ifndef BUILD_CONFIG_UTILITY
#define BUILD_CONFIG_UTILITY
#include <string>
#include <utility> // pair
#include <build/types>
#include <build/diagnostics>
namespace build
{
class scope;
class list_value;
namespace config
{
// Set, if necessary, a required config.* variable.
//
// Return the reference to the value as well as the indication of
// whether the variable has actually been set.
//
template <typename T>
std::pair<const T&, bool>
required (scope& root, const char* name, const T& default_value);
template <typename T>
inline std::pair<const T&, bool>
required (scope& root, const std::string& name, const T& default_value)
{
return required<T> (root, name.c_str (), default_value);
}
std::pair<const std::string&, bool>
required (scope& root, const char* name, const char* default_value);
// Set, if necessary, an optional config.* variable. In particular,
// an unspecified variable is set to NULL which is used to distinguish
// between the "configured as unspecified" and "not yet configured"
// cases.
//
// Return the pointer to the value, which can be NULL.
//
template <typename T>
const T*
optional (scope& root, const char* name);
template <typename T>
inline const T*
optional (scope& root, const std::string& name)
{
return optional<T> (root, name.c_str ());
}
// Check whether there are any variables specified from the
// config namespace. The idea is that we can check if there
// are any, say, config.install.* values. If there are none,
// then we can assume this functionality is not (yet) used
// and omit writing a whole bunch of NULL config.install.*
// values to config.build. We call it omitted/delayed
// configuration.
//
bool
specified (scope& root, const std::string& ns);
// @@ Why are these here?
//
// Add all the values from a variable to the C-string list. T is
// either target or scope.
//
template <typename T>
void
append_options (cstrings& args, T& s, const char* var);
// As above but from the list value directly. Variable name is for
// diagnostics.
//
void
append_options (cstrings& args, const list_value&, const char* var);
// Check if a specified option is present. T is either target or scope.
//
template <typename T>
bool
find_option (const char* option, T& s, const char* var);
}
}
#include <build/config/utility.txx>
#endif // BUILD_CONFIG_UTILITY
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