klammertext/mac/argument.h

#pragma once

#include "argtype.h"

// The Parameter class describes both parameters (in definitions) and
// arguments (in applications). Parameters are the primary concept:
// a designer declares parameters, and a writer supplies arguments to
// fill them. The class is named for the definition side because
// definitions come first; the Argument alias is used at application sites.
class Parameter
{
public:
    Parameter()
        : m_name("_default")
        , m_argtype(Argtype())
        , m_optional(false)
        , m_default("")
        , m_loc()
        , m_target()
        {};

    Parameter(const std::string& name, const Argtype& argtype, const Locator& loc,
             bool optional=false, const std::string& default_value = "");
    ~Parameter() = default;

    bool undefined() const { return m_name == "_default"; };

    std::string m_name {};
    Argtype m_argtype; // {};
    bool m_optional {};
    std::string m_default {};
    // Where m_default came from, for kdesc provenance display.  Default
    // resolution has three levels -- the argument type's :default, an option
    // set's declaration, and the site where the set is used (or the klammer's
    // own parameter list) -- and a reader of kdesc is entitled to know which
    // one produced the value a klammer will use when the argument is absent.
    // True when m_default was filled from the argument type's :default:
    bool m_default_from_type {};
    // The option set (".o" target) this parameter was declared in; empty when
    // it was declared in the klammer's own parameter list.
    std::string m_option_set {};
    // True when the option set declares a default for this parameter and the
    // declaration using the set overrode it.
    bool m_default_overridden {};
    Locator m_loc;
    std::string m_target {};
};

using Argument = Parameter;