cppfig::IsSetting Concept Reference

Concept for valid setting types. More...

#include <setting.h>

Concept definition

template<typename S>
concept cppfig::IsSetting =  requires {
    { S::path } -> std::convertible_to<std::string_view>;
    typename S::value_type;
    { S::default_value() } -> std::same_as<typename S::value_type>;
} && Configurable<typename S::value_type>

Detailed Description

Concept for valid setting types.

A type satisfies IsSetting if it provides all required static members and functions for configuration management.

Required:

• path: std::string_view with the hierarchical key path
• value_type: The type of the setting value
• default_value(): Static function returning the default value

Optional:

• env_override: std::string_view with environment variable name
• validator(): Static function returning a Validator<value_type>

Example:

struct ServerHost {
    static constexpr std::string_view path = "server.host";
    static constexpr std::string_view env_override = "SERVER_HOST";
    using value_type = std::string;
    static auto default_value() -> value_type { return "localhost"; }
    static auto validator() -> Validator<value_type> { return NotEmpty(); }
};