晋太元中,武陵人捕鱼为业。缘溪行,忘路之远近。忽逢桃花林,夹岸数百步,中无杂树,芳草鲜美,落英缤纷。渔人甚异之,复前行,欲穷其林。 林尽水源,便得一山,山有小口,仿佛若有光。便舍船,从口入。初极狭,才通人。复行数十步,豁然开朗。土地平旷,屋舍俨然,有良田、美池、桑竹之属。阡陌交通,鸡犬相闻。其中往来种作,男女衣着,悉如外人。黄发垂髫,并怡然自乐。 见渔人,乃大惊,问所从来。具答之。便要还家,设酒杀鸡作食。村中闻有此人,咸来问讯。自云先世避秦时乱,率妻子邑人来此绝境,不复出焉,遂与外人间隔。问今是何世,乃不知有汉,无论魏晋。此人一一为具言所闻,皆叹惋。余人各复延至其家,皆出酒食。停数日,辞去。此中人语云:“不足为外人道也。”(间隔 一作:隔绝) 既出,得其船,便扶向路,处处志之。及郡下,诣太守,说如此。太守即遣人随其往,寻向所志,遂迷,不复得路。 南阳刘子骥,高尚士也,闻之,欣然规往。未果,寻病终。后遂无问津者。
| DIR:/opt/alt/ruby31/include/ruby/internal/core/ |
| Current File : //opt/alt/ruby31/include/ruby/internal/core/rregexp.h |
#ifndef RBIMPL_RREGEXP_H /*-*-C++-*-vi:se ft=cpp:*/
#define RBIMPL_RREGEXP_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 Defines struct ::RRegexp.
*/
#include "ruby/internal/attr/artificial.h"
#include "ruby/internal/attr/pure.h"
#include "ruby/internal/cast.h"
#include "ruby/internal/core/rbasic.h"
#include "ruby/internal/core/rstring.h"
#include "ruby/internal/value.h"
#include "ruby/internal/value_type.h"
/**
* Convenient casting macro.
*
* @param obj An object, which is in fact an ::RRegexp.
* @return The passed object casted to ::RRegexp.
*/
#define RREGEXP(obj) RBIMPL_CAST((struct RRegexp *)(obj))
/**
* Convenient accessor macro.
*
* @param obj An object, which is in fact an ::RRegexp.
* @return The passed object's pattern buffer.
*/
#define RREGEXP_PTR(obj) (RREGEXP(obj)->ptr)
/** @cond INTERNAL_MACRO */
#define RREGEXP_SRC RREGEXP_SRC
#define RREGEXP_SRC_PTR RREGEXP_SRC_PTR
#define RREGEXP_SRC_LEN RREGEXP_SRC_LEN
#define RREGEXP_SRC_END RREGEXP_SRC_END
/** @endcond */
struct re_patter_buffer; /* a.k.a. OnigRegexType, defined in onigmo.h */
/**
* Ruby's regular expression. A regexp is compiled into its own intermediate
* representation. This one holds that info. Regexp "match" operation then
* executes that IR.
*/
struct RRegexp {
/** Basic part, including flags and class. */
struct RBasic basic;
/**
* The pattern buffer. This is a quasi-opaque struct that holds compiled
* intermediate representation of the regular expression.
*
* @note Compilation of a regexp could be delayed until actual match.
*/
struct re_pattern_buffer *ptr;
/** Source code of this expression. */
const VALUE src;
/**
* Reference count. A regexp match can take extraordinarily long time to
* run. Ruby's regular expression is heavily extended and not a regular
* language any longer; runs in NP-time in practice. Now, Ruby also has
* threads and GVL. In order to prevent long GVL lockup, our regexp engine
* can release it on occasions. This means that multiple threads can touch
* a regular expressions at once. That itself is okay. But their cleanup
* phase shall wait for all the concurrent runs, to prevent use-after-free
* situation. This field is used to count such threads that are executing
* this particular pattern buffer.
*
* @warning Of course, touching this field from extension libraries causes
* catastrophic effects. Just leave it.
*/
unsigned long usecnt;
};
RBIMPL_ATTR_PURE_UNLESS_DEBUG()
RBIMPL_ATTR_ARTIFICIAL()
/**
* Convenient getter function.
*
* @param[in] rexp The regular expression in question.
* @return The source code of the regular expression.
* @pre `rexp` must be of ::RRegexp.
*/
static inline VALUE
RREGEXP_SRC(VALUE rexp)
{
RBIMPL_ASSERT_TYPE(rexp, RUBY_T_REGEXP);
VALUE ret = RREGEXP(rexp)->src;
RBIMPL_ASSERT_TYPE(ret, RUBY_T_STRING);
return ret;
}
RBIMPL_ATTR_PURE_UNLESS_DEBUG()
RBIMPL_ATTR_ARTIFICIAL()
/**
* Convenient getter function.
*
* @param[in] rexp The regular expression in question.
* @return The source code of the regular expression, in C's string.
* @pre `rexp` must be of ::RRegexp.
*
* @internal
*
* It seems nobody uses this function in the wild. Subject to hide?
*/
static inline char *
RREGEXP_SRC_PTR(VALUE rexp)
{
return RSTRING_PTR(RREGEXP_SRC(rexp));
}
RBIMPL_ATTR_PURE_UNLESS_DEBUG()
RBIMPL_ATTR_ARTIFICIAL()
/**
* Convenient getter function.
*
* @param[in] rexp The regular expression in question.
* @return The length of the source code of the regular expression.
* @pre `rexp` must be of ::RRegexp.
*
* @internal
*
* It seems nobody uses this function in the wild. Subject to hide?
*/
static inline long
RREGEXP_SRC_LEN(VALUE rexp)
{
return RSTRING_LEN(RREGEXP_SRC(rexp));
}
RBIMPL_ATTR_PURE_UNLESS_DEBUG()
RBIMPL_ATTR_ARTIFICIAL()
/**
* Convenient getter function.
*
* @param[in] rexp The regular expression in question.
* @return The end of the source code of the regular expression.
* @pre `rexp` must be of ::RRegexp.
*
* @internal
*
* It seems nobody uses this function in the wild. Subject to hide?
*/
static inline char *
RREGEXP_SRC_END(VALUE rexp)
{
return RSTRING_END(RREGEXP_SRC(rexp));
}
#endif /* RBIMPL_RREGEXP_H */
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