1 /* Copyright (c) 2016. The SimGrid Team.
2 * All rights reserved. */
4 /* This program is free software; you can redistribute it and/or modify it
5 * under the terms of the license (GNU LGPL) which comes with this package. */
7 #ifndef _XBT_CONFIG_HPP_
8 #define _XBT_CONFIG_HPP_
13 #include <initializer_list>
16 #include <type_traits>
20 #include <xbt/config.h>
25 template<class T> inline
26 std::string to_string(T&& value)
28 return std::to_string(std::forward<T>(value));
30 inline std::string const& to_string(std::string& value)
34 inline std::string const& to_string(std::string const& value)
38 inline std::string to_string(std::string&& value)
40 return std::move(value);
46 XBT_PUBLIC(T const&) getConfig(const char* name);
48 extern template XBT_PUBLIC(int const&) getConfig<int>(const char* name);
49 extern template XBT_PUBLIC(double const&) getConfig<double>(const char* name);
50 extern template XBT_PUBLIC(bool const&) getConfig<bool>(const char* name);
51 extern template XBT_PUBLIC(std::string const&) getConfig<std::string>(const char* name);
55 /** Register a configuration flag
57 * @param name name of the option
58 * @param description Description of the option
59 * @param value Initial/default value
60 * @param callback called with the option value
63 XBT_PUBLIC(void) declareFlag(const char* name, const char* description,
64 T value, std::function<void(const T&)> callback = std::function<void(const T&)>());
66 extern template XBT_PUBLIC(void) declareFlag(const char* name,
67 const char* description, int value, std::function<void(int const &)> callback);
68 extern template XBT_PUBLIC(void) declareFlag(const char* name,
69 const char* description, double value, std::function<void(double const &)> callback);
70 extern template XBT_PUBLIC(void) declareFlag(const char* name,
71 const char* description, bool value, std::function<void(bool const &)> callback);
72 extern template XBT_PUBLIC(void) declareFlag(const char* name,
73 const char* description, std::string value, std::function<void(std::string const &)> callback);
77 XBT_PUBLIC(void) alias(const char* realname, const char* aliasname);
80 void alias(std::initializer_list<const char*> names)
82 auto i = names.begin();
83 for (++i; i != names.end(); ++i)
84 alias(*names.begin(), *i);
87 /** Bind a variable to configuration flag
89 * @param value Bound variable
90 * @param name Flag name
91 * @param description Option description
94 void bindFlag(T& value, const char* name, const char* description)
97 declareFlag<T>(name, description, value, [&value](T const& val) {
103 void bindFlag(T& value, std::initializer_list<const char*> names, const char* description)
105 bindFlag(value, *names.begin(), description);
109 /** Bind a variable to configuration flag
113 * simgrid::config::bindFlag(a, "x", [](int x) {
114 * if (x < x_min || x => x_max)
115 * throw std::range_error("must be in [x_min, x_max)")
119 // F is a checker, F : T& -> ()
120 template<class T, class F>
121 typename std::enable_if<std::is_same<
123 decltype( std::declval<F>()(std::declval<const T&>()) )
124 >::value, void>::type
125 bindFlag(T& value, std::initializer_list<const char*> names, const char* description,
128 bindFlag(value, *names.begin(), description);
132 template<class T, class F>
133 typename std::enable_if<std::is_same<
135 decltype( std::declval<F>()(std::declval<const T&>()) )
136 >::value, void>::type
137 bindFlag(T& value, const char* name, const char* description,
140 declareFlag(name, description, value, [&value,callback](const T& val) {
142 value = std::move(val);
146 /** Bind a variable to configuration flag
150 * simgrid::config::bindFlag(a, "x", [](int x) { return return x > 0; });
153 // F is a predicate, F : T const& -> bool
154 template<class T, class F>
155 typename std::enable_if<std::is_same<
157 decltype( std::declval<F>()(std::declval<const T&>()) )
158 >::value, void>::type
159 bindFlag(T& value, const char* name, const char* description,
162 declareFlag(name, description, value, [&value,callback](const T& val) {
164 throw std::range_error("invalid value");
165 value = std::move(val);
169 /** A variable bound to a CLI option
172 * static simgrid::config::flag<int> answer("answer", "Expected answer", 42);
173 * static simgrid::config::flag<std::string> name("name", "Ford Prefect", "John Doe");
174 * static simgrid::config::flag<double> gamma("gamma", "Gamma factor", 1.987);
184 * @param name Flag name
185 * @param desc Flag description
186 * @param value Flag initial/default value
188 Flag(const char* name, const char* desc, T value) : value_(value)
190 simgrid::config::bindFlag(value_, name, desc);
194 Flag(const char* name, const char* desc, T value, F callback) : value_(value)
196 simgrid::config::bindFlag(value_, name, desc, std::move(callback));
200 Flag(Flag const&) = delete;
201 Flag& operator=(Flag const&) = delete;
203 // Get the underlying value:
204 T& get() { return value_; }
205 T const& get() const { return value_; }
207 // Implicit conversion to the underlying type:
208 operator T&() { return value_; }
209 operator T const&() const{ return value_; }
211 // Basic interop with T:
212 Flag& operator=(T const& that) { value_ = that; return *this; }
213 Flag& operator=(T && that) { value_ = that; return *this; }
214 bool operator==(T const& that) const { return value_ == that; }
215 bool operator!=(T const& that) const { return value_ != that; }
216 bool operator<(T const& that) const { return value_ < that; }
217 bool operator>(T const& that) const { return value_ > that; }
218 bool operator<=(T const& that) const { return value_ <= that; }
219 bool operator>=(T const& that) const { return value_ >= that; }