Current File : //opt/alt/ruby32/include/ruby/internal/intern/variable.h
#ifndef RBIMPL_INTERN_VARIABLE_H /*-*-C++-*-vi:se ft=cpp:*/
#define RBIMPL_INTERN_VARIABLE_H
/**
* @file
* @author Ruby developers <ruby-core@ruby-lang.org>
* @copyright This file is a part of the programming language Ruby.
* Permission is hereby granted, to either redistribute and/or
* modify this file, provided that the conditions mentioned in the
* file COPYING are met. Consult the file for details.
* @warning Symbols prefixed with either `RBIMPL` or `rbimpl` are
* implementation details. Don't take them as canon. They could
* rapidly appear then vanish. The name (path) of this header file
* is also an implementation detail. Do not expect it to persist
* at the place it is now. Developers are free to move it anywhere
* anytime at will.
* @note To ruby-core: remember that this header can be possibly
* recursively included from extension libraries written in C++.
* Do not expect for instance `__VA_ARGS__` is always available.
* We assume C99 for ruby itself but we don't assume languages of
* extension libraries. They could be written in C++98.
* @brief Public APIs related to names inside of a Ruby program.
*/
#include "ruby/internal/attr/nonnull.h"
#include "ruby/internal/attr/noreturn.h"
#include "ruby/internal/dllexport.h"
#include "ruby/internal/value.h"
#include "ruby/st.h"
RBIMPL_SYMBOL_EXPORT_BEGIN()
/* variable.c */
/**
* Queries the name of a module.
*
* @param[in] mod An instance of ::rb_cModule.
* @retval RUBY_Qnil `mod` is anonymous.
* @retval otherwise `mod` is onymous.
*/
VALUE rb_mod_name(VALUE mod);
/**
* Identical to rb_mod_name(), except it returns `#<Class: ...>` style
* inspection for anonymous modules.
*
* @param[in] mod An instance of ::rb_cModule.
* @return An instance of ::rb_cString representing `mod`'s path.
*/
VALUE rb_class_path(VALUE mod);
/**
* @alias{rb_mod_name}
*
* @internal
*
* Am I missing something? Why we have the same thing in different names?
*/
VALUE rb_class_path_cached(VALUE mod);
RBIMPL_ATTR_NONNULL(())
/**
* Names a class.
*
* @param[out] klass Target module to name.
* @param[out] space Namespace that `klass` shall reside.
* @param[in] name Name of `klass`.
* @post `klass` has `space::klass` name.
*/
void rb_set_class_path(VALUE klass, VALUE space, const char *name);
/**
* Identical to rb_set_class_path(), except it accepts the name as Ruby's
* string instead of C's.
*
* @param[out] klass Target module to name.
* @param[out] space Namespace that `klass` shall reside.
* @param[in] name Name of `klass`.
* @post `klass` has `space::klass` name.
*/
void rb_set_class_path_string(VALUE klass, VALUE space, VALUE name);
/**
* Identical to rb_path2class(), except it accepts the path as Ruby's string
* instead of C's.
*
* @param[in] path Path to query.
* @exception rb_eArgError No such constant.
* @exception rb_eTypeError The path resolved to a non-module.
* @return Resolved class.
*/
VALUE rb_path_to_class(VALUE path);
RBIMPL_ATTR_NONNULL(())
/**
* Resolves a `Q::W::E::R`-style path string to the actual class it points.
*
* @param[in] path Path to query.
* @exception rb_eArgError No such constant.
* @exception rb_eTypeError The path resolved to a non-module.
* @return Resolved class.
*/
VALUE rb_path2class(const char *path);
/**
* Queries the name of the given object's class.
*
* @param[in] obj Arbitrary object.
* @return An instance of ::rb_cString representing `obj`'s class' path.
*/
VALUE rb_class_name(VALUE obj);
/**
* Kicks the autoload procedure as if it was "touched".
*
* @param[out] space Namespace where autoload is defined.
* @param[in] name Name of the autoloaded constant.
* @retval RUBY_Qfalse No such autoload.
* @retval RUBY_Qtrue Autoload successfully initiated.
* @note As an autoloaded library is expected to define `space::name`,
* it is a nature of this function to have process-global side
* effects.
* @note Multiple threads can simultaneously call this API. It blocks
* then. That must not last indefinitely but can take longer than
* you expect.
*
* @internal
*
* @shyouhei has no idea why extension libraries should use this API.
*/
VALUE rb_autoload_load(VALUE space, ID name);
/**
* Queries if an autoload is defined at a point.
*
* @param[in] space Namespace where autoload is defined.
* @param[in] name Name of the autoloaded constant.
* @retval RUBY_Qnil No such autoload.
* @retval otherwise The feature (path) registered at `space::name`.
*/
VALUE rb_autoload_p(VALUE space, ID name);
/**
* Traces a global variable.
*
* @param[in] argc Either 1 or 2.
* @param[in] argv Variable name, optionally a Proc.
* @retval RUBY_Qnil No previous tracers.
* @retval otherwise Previous tracers.
*
* @internal
*
* @shyouhei has no idea why extension libraries should use this API.
*/
VALUE rb_f_trace_var(int argc, const VALUE *argv);
/**
* Deletes the passed tracer from the passed global variable, or if omitted,
* deletes everything.
*
* @param[in] argc Either 1 or 2.
* @param[in] argv Variable name, optionally a Proc.
* @retval RUBY_Qnil No previous tracers.
* @retval otherwise Deleted tracers.
*
* @internal
*
* @shyouhei has no idea why extension libraries should use this API.
*/
VALUE rb_f_untrace_var(int argc, const VALUE *argv);
/**
* Queries the list of global variables.
*
* @return The list of the name of the global variables.
*
* @internal
*
* Above description is in fact inaccurate. This API interfaces with Ractors.
*/
VALUE rb_f_global_variables(void);
/**
* Aliases a global variable. Did you know that you can alias a global
* variable? It is like aliasing methods:
*
* ```ruby
* alias $dst $src
* ```
*
* This C function does the same thing.
*
* @param[in] dst Destination name.
* @param[in] src Source name.
* @post A global variable named `dst` is defined to be an alias of a
* global variable named `src`.
*
* @internal
*
* Above description is in fact inaccurate. This API interfaces with Ractors.
*/
void rb_alias_variable(ID dst, ID src);
/**
* Frees the list of instance variables. 3rd parties need not know, but there
* are several ways to store an object's instance variables, depending on its
* internal structure. This function makes sense when the passed objects is
* using so-called "generic" backend storage. People need not be aware of this
* working behind-the-scenes.
*
* @param[out] obj The object in question.
*
* @internal
*
* This just destroys the given object. @shyouhei has no idea why extension
* libraries should use this API.
*/
void rb_free_generic_ivar(VALUE obj);
/**
* Identical to rb_iv_get(), except it accepts the name as an ::ID instead of a
* C string.
*
* @param[in] obj Target object.
* @param[in] name Target instance variable to query.
* @retval RUBY_nil No such instance variable.
* @retval otherwise The value assigned to the instance variable.
*/
VALUE rb_ivar_get(VALUE obj, ID name);
/**
* Identical to rb_iv_set(), except it accepts the name as an ::ID instead of a
* C string.
*
* @param[out] obj Target object.
* @param[in] name Target instance variable.
* @param[in] val Value to assign.
* @exception rb_eFrozenError Can't modify `obj`.
* @exception rb_eArgError `obj` has too many instance variables.
* @return Passed value.
* @post An instance variable named `name` is defined if absent on
* `obj`, whose value is set to `val`.
*/
VALUE rb_ivar_set(VALUE obj, ID name, VALUE val);
/**
* Queries if the instance variable is defined at the object. This roughly
* resembles `defined?(@name)` in `obj`'s context.
*
* @param[in] obj Target object.
* @param[in] name Target instance variable to query.
* @retval RUBY_Qtrue There is an instance variable.
* @retval RUBY_Qfalse No such instance variable.
*/
VALUE rb_ivar_defined(VALUE obj, ID name);
/**
* Iterates over an object's instance variables.
*
* @param[in] obj Target object.
* @param[in] func Callback function.
* @param[in] arg Passed as-is to the last argument of `func`.
*/
void rb_ivar_foreach(VALUE obj, int (*func)(ID name, VALUE val, st_data_t arg), st_data_t arg);
/**
* Number of instance variables defined on an object.
*
* @param[in] obj Target object.
* @return Number of instance variables defined on `obj`.
*/
st_index_t rb_ivar_count(VALUE obj);
/**
* Identical to rb_ivar_get()
*
* @param[in] obj Target object.
* @param[in] name Target instance variable to query.
* @retval RUBY_nil No such instance variable.
* @retval otherwise The value assigned to the instance variable.
*
* @internal
*
* Am I missing something? Why we have the same thing in different names?
*/
VALUE rb_attr_get(VALUE obj, ID name);
/**
* Resembles `Object#instance_variables`.
*
* @param[in] obj Target object to query.
* @return An array of instance variable names for the receiver.
* @note Simply defining an accessor does not create the corresponding
* instance variable.
*/
VALUE rb_obj_instance_variables(VALUE obj);
/**
* Resembles `Object#remove_instance_variable`.
*
* @param[out] obj Target object.
* @param[in] name Variable name to remove, either in Symbol or String.
* @return What was removed.
* @pre Instance variable named `name` is deleted from `obj`.
*/
VALUE rb_obj_remove_instance_variable(VALUE obj, VALUE name);
/**
* This API is mysterious. It has been there since the initial revision. No
* single bits of documents has ever been written. The function name doesn't
* describe anything. What should be passed to the argument, or what should be
* the return value, are not obvious. Yet it has evolved over time. The
* source code is written in counter-intuitive way (as of 3.0).
*
* Simply put, don't try to understand this API.
*/
void *rb_mod_const_at(VALUE, void*);
/**
* This is a variant of rb_mod_const_at(). As a result, it is also mysterious.
* It _seems_ it iterates over the ancestry tree of the module. But what that
* means is beyond a human brain.
*/
void *rb_mod_const_of(VALUE, void*);
/**
* This is another mysterious API that comes with no documents at all. It
* seems it expects some specific data structure for the passed pointer. But
* the details has never been made explicit. It seems nobody should use this
* API.
*/
VALUE rb_const_list(void*);
/**
* Resembles `Module#constants`. List up the constants defined at the
* receiver. This includes the names of constants in any included modules,
* unless `argv[0]` is ::RUBY_Qfalse.
*
* The implementation makes no guarantees about the order in which the
* constants are yielded.
*
* @param[in] argc Either 0 or 1.
* @param[in] argv Pointer to ::RUBY_Qfalse, if `argc == 1`.
* @param[in] recv Target namespace.
* @return An array of symbols, which are constant names under `recv`.
*/
VALUE rb_mod_constants(int argc, const VALUE *argv, VALUE recv);
/**
* Resembles `Module#remove_const`.
*
* @param[out] space Target namespace.
* @param[in] name Variable name to remove, either in Symbol or String.
* @return What was removed.
* @pre Constant named `space::name` is deleted.
* @note In case what was removed was in fact a module or a class, this
* operation does not affect its name. Which means when people
* for instance look at it using `p` etc., it still introduces
* itself using the deleted name. Can confuse people.
*/
VALUE rb_mod_remove_const(VALUE space, VALUE name);
/**
* Queries if the constant is defined at the namespace.
*
* @param[in] space Target namespace.
* @param[in] name Target name to query.
* @retval RUBY_Qtrue There is a constant.
* @retval RUBY_Qfalse No such constant.
*
* @internal
*
* The return values are not typo! This function returns ruby values casted to
* `int`. Completely brain-damaged design.
*/
int rb_const_defined(VALUE space, ID name);
/**
* Identical to rb_const_defined(), except it doesn't look for parent classes.
* For instance `Array` is a toplevel constant, which is visible from
* everywhere. But this function does not take such things into account. It
* concerns only what is directly defined inside of the given namespace.
*
* @param[in] space Target namespace.
* @param[in] name Target name to query.
* @retval RUBY_Qtrue There is a constant.
* @retval RUBY_Qfalse No such constant.
*
* @internal
*
* The return values are not typo! This function returns ruby values casted to
* `int`. Completely brain-damaged design.
*/
int rb_const_defined_at(VALUE space, ID name);
/**
* Identical to rb_const_defined(), except it returns false for private
* constants.
*
* @param[in] space Target namespace.
* @param[in] name Target name to query.
* @retval RUBY_Qtrue There is a constant.
* @retval RUBY_Qfalse No such constant.
*
* @internal
*
* What does "from" mean? The name sounds quite cryptic.
*
* The return values are not typo! This function returns ruby values casted to
* `int`. Completely brain-damaged design.
*/
int rb_const_defined_from(VALUE space, ID name);
/**
* Identical to rb_const_defined(), except it returns the actual defined value.
*
* @param[in] space Target namespace.
* @param[in] name Target name to query.
* @exception rb_eNameError No such constant.
* @return The defined constant.
*
* @internal
*
* Above description is in fact inaccurate. This API interfaces with Ractors.
*/
VALUE rb_const_get(VALUE space, ID name);
/**
* Identical to rb_const_defined_at(), except it returns the actual defined
* value. It can also be seen as a routine identical to rb_const_get(), except
* it doesn't look for parent classes.
*
* @param[in] space Target namespace.
* @param[in] name Target name to query.
* @exception rb_eNameError No such constant.
* @return The defined constant.
*
* @internal
*
* Above description is in fact inaccurate. This API interfaces with Ractors.
*/
VALUE rb_const_get_at(VALUE space, ID name);
/**
* Identical to rb_const_defined_at(), except it returns the actual defined
* value. It can also be seen as a routine identical to rb_const_get(), except
* it doesn't return a private constant.
*
* @param[in] space Target namespace.
* @param[in] name Target name to query.
* @exception rb_eNameError No such constant.
* @return The defined constant.
*
* @internal
*
* Above description is in fact inaccurate. This API interfaces with Ractors.
*/
VALUE rb_const_get_from(VALUE space, ID name);
/**
* Names a constant.
*
* @param[out] space Target namespace.
* @param[in] name Target name to query.
* @param[in] val Value to define.
* @exception rb_eTypeError `space` is not a module.
* @post `name` is a constant under `space`, whose value is `val`.
* @note You can reassign.
*
* @internal
*
* Above description is in fact inaccurate. This API interfaces with Ractors.
*/
void rb_const_set(VALUE space, ID name, VALUE val);
/**
* Identical to rb_mod_remove_const(), except it takes the name as ::ID instead
* of ::VALUE.
*
* @param[out] space Target namespace.
* @param[in] name Variable name to remove, either in Symbol or String.
* @return What was removed.
* @pre Constant named `space::name` is deleted.
* @note In case what was removed was in fact a module or a class, this
* operation does not affect its name. Which means when people
* for instance look at it using `p` etc., it still introduces
* itself using the deleted name. Can confuse people.
*/
VALUE rb_const_remove(VALUE space, ID name);
#if 0 /* EXPERIMENTAL: remove if no problem */
RBIMPL_ATTR_NORETURN()
/**
* This is the default implementation of `Module#const_missing`.
*
* @param[in] space Target namespace.
* @param[in] name Target name that is nonexistent.
* @exception rb_eNameError Always.
*/
VALUE rb_mod_const_missing(VALUE space, VALUE name);
#endif
/**
* Queries if the given class has the given class variable.
*
* @param[in] klass Target class.
* @param[in] name Name to query.
* @return RUBY_Qtrue Yes there is.
* @return RUBY_Qfalse No there isn't.
* @pre `klass` must be an instance of rb_cModule.
*
* @internal
*
* Above description is in fact inaccurate. This API interfaces with Ractors.
*/
VALUE rb_cvar_defined(VALUE klass, ID name);
/**
* Assigns a value to a class variable.
*
* @param[out] klass Target class.
* @param[in] name Variable name.
* @param[in] val Value to be assigned.
* @post `klass` has a class variable named `name` whose value is `val`.
*
* @internal
*
* Above description is in fact inaccurate. This API interfaces with Ractors.
*/
void rb_cvar_set(VALUE klass, ID name, VALUE val);
/**
* Obtains a value from a class variable.
*
* @param[in] klass Target class.
* @param[in] name Variable name.
* @exception rb_eNameError Uninitialised class variable.
* @exception rb_eRuntimeError `[Bug#14541]` situation.
* @return Class variable named `name` under `klass`.
*
* @internal
*
* Above description is in fact inaccurate. This API interfaces with Ractors.
*/
VALUE rb_cvar_get(VALUE klass, ID name);
RBIMPL_ATTR_NONNULL(())
/**
* Identical to rb_cvar_get(), except it takes additional "front" pointer.
* This extra parameter is a buffer, which will have the class where the
* queried class variable actually resides.
*
* @param[in] klass Target class.
* @param[in] name Variable name.
* @param[out] front Return buffer.
* @exception rb_eNameError Uninitialised class variable.
* @exception rb_eRuntimeError `[Bug#14541]` situation.
* @return Class variable named `name` under `klass`.
* @post `front` has the class object, which is an ancestor of `klass`,
* where the queried class variable actually resides.
*
* @internal
*
* Above description is in fact inaccurate. This API interfaces with Ractors.
*/
VALUE rb_cvar_find(VALUE klass, ID name, VALUE *front);
RBIMPL_ATTR_NONNULL(())
/**
* Identical to rb_cvar_set(), except it accepts C's string instead of ::ID.
*
* @param[out] klass Target class.
* @param[in] name Variable name.
* @param[in] val Value to be assigned.
* @post `klass` has a class variable named `name` whose value is `val`.
*/
void rb_cv_set(VALUE klass, const char *name, VALUE val);
RBIMPL_ATTR_NONNULL(())
/**
* Identical to rb_cvar_get(), except it accepts C's string instead of ::ID.
*
* @param[in] klass Target class.
* @param[in] name Variable name.
* @exception rb_eNameError Uninitialised class variable.
* @exception rb_eRuntimeError `[Bug#14541]` situation.
* @return Class variable named `name` under `klass`.
*/
VALUE rb_cv_get(VALUE klass, const char *name);
RBIMPL_ATTR_NONNULL(())
/**
* @alias{rb_cv_set}
*
* @internal
*
* Am I missing something? Why we have the same thing in different names?
*/
void rb_define_class_variable(VALUE, const char*, VALUE);
/**
* Resembles `Module#class_variables`. List up the variables defined at the
* receiver. This includes the names of constants in any included modules,
* unless `argv[0]` is ::RUBY_Qfalse.
*
* The implementation makes no guarantees about the order in which the
* constants are yielded.
*
* @param[in] argc Either 0 or 1.
* @param[in] argv Pointer to ::RUBY_Qfalse, if `argc == 1`.
* @param[in] recv Target class.
* @return An array of symbols, which are class variable names under
* `recv`.
*/
VALUE rb_mod_class_variables(int argc, const VALUE *argv, VALUE recv);
/**
* Resembles `Module#remove_class_variable`.
*
* @param[out] mod Target class.
* @param[in] name Variable name to remove, either in Symbol or String.
* @return What was removed.
* @pre Instance variable named `name` is deleted from `obj`.
*/
VALUE rb_mod_remove_cvar(VALUE mod, VALUE name);
RBIMPL_SYMBOL_EXPORT_END()
#endif /* RBIMPL_INTERN_VARIABLE_H */