AlkantarClanX12
Current Path : /opt/alt/ruby32/include/ruby/internal/ |
Current File : //opt/alt/ruby32/include/ruby/internal/iterator.h |
#ifndef RBIMPL_ITERATOR_H /*-*-C++-*-vi:se ft=cpp:*/ #define RBIMPL_ITERATOR_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 Block related APIs. */ #include "ruby/internal/attr/deprecated.h" #include "ruby/internal/attr/noreturn.h" #include "ruby/internal/dllexport.h" #include "ruby/internal/value.h" RBIMPL_SYMBOL_EXPORT_BEGIN() /** * @private * * @deprecated This macro once was a thing in the old days, but makes no sense * any longer today. Exists here for backwards compatibility * only. You can safely forget about it. */ #define RB_BLOCK_CALL_FUNC_STRICT 1 /** * @private * * @deprecated This macro once was a thing in the old days, but makes no sense * any longer today. Exists here for backwards compatibility * only. You can safely forget about it. */ #define RUBY_BLOCK_CALL_FUNC_TAKES_BLOCKARG 1 /** * Shim for block function parameters. Historically ::rb_block_call_func_t had * only two parameters. Over time it evolved to have much more than that. By * using this macro you can absorb such API differences. * * ```CXX * // This works since 2.1.0 * VALUE my_own_iterator(RB_BLOCK_CALL_FUNC_ARGLIST(y, c)); * ``` */ #define RB_BLOCK_CALL_FUNC_ARGLIST(yielded_arg, callback_arg) \ VALUE yielded_arg, VALUE callback_arg, int argc, const VALUE *argv, VALUE blockarg /** * This is the type of a function that the interpreter expect for C-backended * blocks. Blocks are often written in Ruby. But C extensions might want to * have their own blocks. In order to do so authors have to create a separate * C function of this type, and pass its pointer to rb_block_call(). * * ```CXX * VALUE * my_own_iterator(RB_BLOCK_CALL_FUNC_ARGLIST(y, c)) * { * const auto plus = rb_intern("+"); * return rb_funcall(c, plus, 1, y); * } * * VALUE * my_own_method(VALUE self) * { * const auto each = rb_intern("each"); * return rb_block_call(self, each, 0, 0, my_own_iterator, self); * } * ``` */ typedef VALUE rb_block_call_func(RB_BLOCK_CALL_FUNC_ARGLIST(yielded_arg, callback_arg)); /** * Shorthand type that represents an iterator-written-in-C function pointer. */ typedef rb_block_call_func *rb_block_call_func_t; /** * This is a shorthand of calling `obj.each`. * * @param[in] obj The receiver. * @return What `obj.each` returns. * * @internal * * Does anyone still need it? This API was to use with rb_iterate(), which is * marked deprecated (see below). Old idiom to call an iterator was: * * ```CXX * VALUE recv; * VALUE iter_func(ANYARGS); * VALUE iter_data; * rb_iterate(rb_each, recv, iter_func, iter_data); * ``` */ VALUE rb_each(VALUE obj); /** * Yields the block. In Ruby there is a concept called a block. You can pass * one to a method. In a method, when called with a block, you can yield it * using this function. * * ```CXX * VALUE * iterate(VALUE self) * { * extern int get_n(VALUE); * extern VALUE get_v(VALUE, VALUE); * const auto n = get_n(self); * * for (int i=0; i<n; i++) { * auto v = get_v(self, i); * * rb_yield(v); * } * return self; * } * ``` * * @param[in] val Passed to the block. * @exception rb_eLocalJumpError There is no block given. * @return Evaluated value of the given block. */ VALUE rb_yield(VALUE val); /** * Identical to rb_yield(), except it takes variadic number of parameters and * pass them to the block. * * @param[in] n Number of parameters. * @param[in] ... List of arguments passed to the block. * @exception rb_eLocalJumpError There is no block given. * @return Evaluated value of the given block. */ VALUE rb_yield_values(int n, ...); /** * Identical to rb_yield_values(), except it takes the parameters as a C array * instead of variadic arguments. * * @param[in] n Number of parameters. * @param[in] argv List of arguments passed to the block. * @exception rb_eLocalJumpError There is no block given. * @return Evaluated value of the given block. */ VALUE rb_yield_values2(int n, const VALUE *argv); /** * Identical to rb_yield_values2(), except you can specify how to handle the * last element of the given array. * * @param[in] n Number of parameters. * @param[in] argv List of arguments passed to the block. * @param[in] kw_splat Handling of keyword parameters: * - RB_NO_KEYWORDS `ary`'s last is not a keyword argument. * - RB_PASS_KEYWORDS `ary`'s last is a keyword argument. * - RB_PASS_CALLED_KEYWORDS makes no sense here. * @exception rb_eLocalJumpError There is no block given. * @return Evaluated value of the given block. */ VALUE rb_yield_values_kw(int n, const VALUE *argv, int kw_splat); /** * Identical to rb_yield_values(), except it splats an array to generate the * list of parameters. * * @param[in] ary Array to splat. * @exception rb_eLocalJumpError There is no block given. * @return Evaluated value of the given block. */ VALUE rb_yield_splat(VALUE ary); /** * Identical to rb_yield_splat(), except you can specify how to handle the last * element of the given array. * * @param[in] ary Array to splat. * @param[in] kw_splat Handling of keyword parameters: * - RB_NO_KEYWORDS `ary`'s last is not a keyword argument. * - RB_PASS_KEYWORDS `ary`'s last is a keyword argument. * - RB_PASS_CALLED_KEYWORDS makes no sense here. * @exception rb_eLocalJumpError There is no block given. * @return Evaluated value of the given block. */ VALUE rb_yield_splat_kw(VALUE ary, int kw_splat); /** * Pass a passed block. * * Sometimes you want to "pass" a block form one method to another. Suppose * you have this Ruby method `foo`: * * ```ruby * def foo(x, y) * x.open(y) do |*z| * yield(*z) * end * end * ``` * * And suppose you want to translate this into C. Then rb_yield_block() * function is usable in this situation. * * ```CXX * VALUE * foo_translated_into_C(VALUE self, VALUE x, VALUE y) * { * const auto open = rb_intern("open"); * * return rb_block_call(x, open, 1, &y, rb_yield_block, Qfalse); * // ^^^^^^^^^^^^^^ Here. * } * ``` * * @see rb_funcall_passing_block * * @internal * * @shyouhei honestly doesn't understand why this is needed, given there * already was rb_funcall_passing_block() at the time it was implemented. If * somebody knows its raison d'etre, please improve the document :FIXME: */ VALUE rb_yield_block(RB_BLOCK_CALL_FUNC_ARGLIST(yielded_arg, callback_arg)); /* rb_block_call_func */ /** * Determines if the current method is given a keyword argument. * * @retval false No keyword argument is given. * @retval true Keyword argument(s) are given. * @ingroup defmethod */ int rb_keyword_given_p(void); /** * Determines if the current method is given a block. * * @retval false No block is given. * @retval true A block is given. * @ingroup defmethod * * @internal * * This function should have returned a bool. But at the time it was designed * the project was entirely written in K&R C. */ int rb_block_given_p(void); /** * Declares that the current method needs a block. * * @exception rb_eLocalJumpError No block given. * @ingroup defmethod */ void rb_need_block(void); #ifndef __cplusplus RBIMPL_ATTR_DEPRECATED(("by: rb_block_call since 1.9")) #endif /** * Old way to iterate a block. * * @deprecated This is an old API. Use rb_block_call() instead. * @warning The passed function must at least once call a ruby method * (to handle interrupts etc.) * @param[in] func1 A function that could yield a value. * @param[in,out] data1 Passed to `func1` * @param[in] proc A function acts as a block. * @param[in,out] data2 Passed to `proc` as the data2 parameter. * @return What `func1` returns. */ VALUE rb_iterate(VALUE (*func1)(VALUE), VALUE data1, rb_block_call_func_t proc, VALUE data2); #ifdef __cplusplus namespace ruby { namespace backward { /** * Old way to iterate a block. * * @deprecated This is an old API. Use rb_block_call() instead. * @warning The passed function must at least once call a ruby method * (to handle interrupts etc.) * @param[in] iter A function that could yield a value. * @param[in,out] data1 Passed to `func1` * @param[in] bl A function acts as a block. * @param[in,out] data2 Passed to `proc` as the data2 parameter. * @return What `func1` returns. */ static inline VALUE rb_iterate_deprecated(VALUE (*iter)(VALUE), VALUE data1, rb_block_call_func_t bl, VALUE data2) { return ::rb_iterate(iter, data1, bl, data2); }}} RBIMPL_ATTR_DEPRECATED(("by: rb_block_call since 1.9")) VALUE rb_iterate(VALUE (*func1)(VALUE), VALUE data1, rb_block_call_func_t proc, VALUE data2); #endif /** * Identical to rb_funcallv(), except it additionally passes a function as a * block. When the method yields, `proc` is called with the yielded value as * its first argument, and `data2` as the second. Yielded values would be * packed into an array if multiple values are yielded at once. * * @param[in,out] obj Receiver. * @param[in] mid Method signature. * @param[in] argc Number of arguments. * @param[in] argv Arguments passed to `obj.mid`. * @param[in] proc A function acts as a block. * @param[in,out] data2 Passed to `proc` as the data2 parameter. * @return What `obj.mid` returns. */ VALUE rb_block_call(VALUE obj, ID mid, int argc, const VALUE *argv, rb_block_call_func_t proc, VALUE data2); /** * Identical to rb_funcallv_kw(), except it additionally passes a function as a * block. It can also be seen as a routine identical to rb_block_call(), * except it handles keyword-ness of `argv[argc-1]`. * * @param[in,out] obj Receiver. * @param[in] mid Method signature. * @param[in] argc Number of arguments including the keywords. * @param[in] argv Arguments passed to `obj.mid`. * @param[in] proc A function acts as a block. * @param[in,out] data2 Passed to `proc` as the data2 parameter. * @param[in] kw_splat Handling of keyword parameters: * - RB_NO_KEYWORDS `argv`'s last is not a keyword argument. * - RB_PASS_KEYWORDS `argv`'s last is a keyword argument. * - RB_PASS_CALLED_KEYWORDS it depends if there is a passed block. * @return What `obj.mid` returns. */ VALUE rb_block_call_kw(VALUE obj, ID mid, int argc, const VALUE *argv, rb_block_call_func_t proc, VALUE data2, int kw_splat); /** * Identical to rb_rescue2(), except it does not take a list of exception * classes. This is a shorthand of: * * ```CXX * rb_rescue2(b_proc, data1, r_proc, data2, rb_eStandardError, (VALUE)0); * ``` * * @param[in] b_proc A function which potentially raises an exception. * @param[in,out] data1 Passed to `b_proc`. * @param[in] r_proc A function which rescues an exception in `b_proc`. * @param[in,out] data2 The first argument of `r_proc`. * @return The return value of `b_proc` if no exception occurs, or the * return value of `r_proc` otherwise. * @see rb_rescue * @see rb_ensure * @see rb_protect * @ingroup exception */ VALUE rb_rescue(VALUE (*b_proc)(VALUE), VALUE data1, VALUE (*r_proc)(VALUE, VALUE), VALUE data2); /** * An equivalent of `rescue` clause. * * First it calls the function `b_proc` with `data1` as the argument. If * nothing is thrown the function happily returns the return value of `b_proc`. * When `b_proc` raises an exception, and the exception is a kind of one of the * given exception classes, it then calls `r_proc` with `data2` and that * exception. If the exception does not match any of them, it propagates. * * @param[in] b_proc A function which potentially raises an exception. * @param[in,out] data1 Passed to `b_proc`. * @param[in] r_proc A function which rescues an exception in `b_proc`. * @param[in,out] data2 The first argument of `r_proc`. * @param[in] ... 1 or more exception classes. Must be terminated by * `(VALUE)0` * @return The return value of `b_proc` if no exception occurs, or the * return value of `r_proc` otherwise. * @see rb_rescue * @see rb_ensure * @see rb_protect * @ingroup exception */ VALUE rb_rescue2(VALUE (*b_proc)(VALUE), VALUE data1, VALUE (*r_proc)(VALUE, VALUE), VALUE data2, ...); /** * Identical to rb_rescue2(), except it takes `va_list` instead of variadic * number of arguments. This is exposed to 3rd parties because inline * functions use it. Basically you don't have to bother. * * @param[in] b_proc A function which potentially raises an exception. * @param[in,out] data1 Passed to `b_proc`. * @param[in] r_proc A function which rescues an exception in `b_proc`. * @param[in,out] data2 The first argument of `r_proc`. * @param[in] ap 1 or more exception classes. Must be terminated by * `(VALUE)0` * @return The return value of `b_proc` if no exception occurs, or the * return value of `r_proc` otherwise. * @see rb_rescue * @see rb_ensure * @see rb_protect * @ingroup exception */ VALUE rb_vrescue2(VALUE (*b_proc)(VALUE), VALUE data1, VALUE (*r_proc)(VALUE, VALUE), VALUE data2, va_list ap); /** * An equivalent to `ensure` clause. Calls the function `b_proc` with `data1` * as the argument, then calls `e_proc` with `data2` when execution terminated. * * @param[in] b_proc A function representing begin clause. * @param[in,out] data1 Passed to `b_proc`. * @param[in] e_proc A function representing ensure clause. * @param[in,out] data2 Passed to `e_proc`. * @retval RUBY_Qnil exception occurred inside of `b_proc`. * @retval otherwise The return value of `b_proc`. * @see rb_rescue * @see rb_rescue2 * @see rb_protect * @ingroup exception */ VALUE rb_ensure(VALUE (*b_proc)(VALUE), VALUE data1, VALUE (*e_proc)(VALUE), VALUE data2); /** * Executes the passed block and catches values thrown from inside of it. * * In case the block does not contain any throw`, this function returns the * value of the last expression evaluated. * * ```CXX * VALUE * iter(RB_BLOCK_CALL_FUNC_ARGLIST(yielded, callback)) * { * return INT2FIX(123); * } * * VALUE * method(VALUE self) * { * return rb_catch("tag", iter, Qnil); // returns 123 * } * ``` * * In case there do exist `throw`, Ruby searches up its execution context for a * `catch` block. When a matching catch is found, the block stops executing * and returns that thrown value instead. * * ```CXX * VALUE * iter(RB_BLOCK_CALL_FUNC_ARGLIST(yielded, callback)) * { * rb_throw("tag", 456); * return INT2FIX(123); * } * * VALUE * method(VALUE self) * { * return rb_catch("tag", iter, Qnil); // returns 456 * } * ``` * * @param[in] tag Arbitrary tag string. * @param[in] func Function pointer that acts as a block. * @param[in,out] data Extra parameter passed to `func`. * @return Either caught value for `tag`, or the return value of `func` * if nothing is thrown. */ VALUE rb_catch(const char *tag, rb_block_call_func_t func, VALUE data); /** * Identical to rb_catch(), except it catches arbitrary Ruby objects. * * @param[in] tag Arbitrary tag object. * @param[in] func Function pointer that acts as a block. * @param[in,out] data Extra parameter passed to `func`. * @return Either caught value for `tag`, or the return value of `func` * if nothing is thrown. */ VALUE rb_catch_obj(VALUE tag, rb_block_call_func_t func, VALUE data); RBIMPL_ATTR_NORETURN() /** * Transfers control to the end of the active `catch` block waiting for `tag`. * Raises rb_eUncughtThrow if there is no `catch` block for the tag. The * second parameter supplies a return value for the `catch` block, which * otherwise defaults to ::RUBY_Qnil. For examples, see rb_catch(). * * @param[in] tag Tag string. * @param[in] val Value to throw. * @exception rb_eUncughtThrow There is no corresponding `catch` clause. * @note It never returns. */ void rb_throw(const char *tag, VALUE val); RBIMPL_ATTR_NORETURN() /** * Identical to rb_throw(), except it allows arbitrary Ruby object to become a * tag. * * @param[in] tag Arbitrary object. * @param[in] val Value to throw. * @exception rb_eUncughtThrow There is no corresponding `catch` clause. * @note It never returns. */ void rb_throw_obj(VALUE tag, VALUE val); RBIMPL_SYMBOL_EXPORT_END() #endif /* RBIMPL_ITERATOR_H */