Ruby 3.2.1p31 (2023-02-08 revision 31819e82c88c6f8ecfaeb162519bfa26a14b21fd)
Data Structures | Macros | Typedefs | Functions
rmatch.h File Reference

Defines struct RMatch. More...

#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/value.h"
#include "ruby/internal/value_type.h"
#include "ruby/assert.h"

Go to the source code of this file.

Data Structures

struct  rmatch_offset
 Represents the region of a capture group. More...
 
struct  rmatch
 Represents a match. More...
 
struct  RMatch
 Regular expression execution context. More...
 

Macros

#define RMATCH(obj)   RBIMPL_CAST((struct RMatch *)(obj))
 Convenient casting macro.
 

Typedefs

typedef struct re_pattern_buffer Regexp
 Old name of re_pattern_buffer.
 

Functions

static struct re_registersRMATCH_REGS (VALUE match)
 Queries the raw re_registers.
 

Detailed Description

Defines struct RMatch.

Author
Ruby developers ruby-.nosp@m.core.nosp@m.@ruby.nosp@m.-lan.nosp@m.g.org
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.

Definition in file rmatch.h.

Macro Definition Documentation

◆ RMATCH

#define RMATCH (   obj)    RBIMPL_CAST((struct RMatch *)(obj))

Convenient casting macro.

Parameters
objAn object, which is in fact an RMatch.
Returns
The passed object casted to RMatch.

Definition at line 37 of file rmatch.h.

Function Documentation

◆ RMATCH_REGS()

static struct re_registers * RMATCH_REGS ( VALUE  match)
inlinestatic

Queries the raw re_registers.

Parameters
[in]matchA match object
Precondition
match must be of RMatch.
Returns
Its execution result.
Note
Good. So you are aware of the fact that it could return NULL. Yes. It actually does. This is a really bizarre thing. The situation is about String#gsub and its family. They take strings as arguments, like "foo".sub("bar", "baz"). On such situations, in order to optimise memory allocations, these methods do not involve regular expressions at all. They just sequentially scan the receiver. Okay. The story begins here. Even when they do not kick our regexp engine, there must be backref objects e.g. $&. But how? You know what? Ruby fakes them. It allocates an empty RMatch and behaves as if there were execution contexts. In reality there weren't. No re_registers are allocated then. There is no way for this function but to return NULL for those fake RMatch. This is the reason for the nullability of this function.

Definition at line 139 of file rmatch.h.

Referenced by rb_reg_match_last(), rb_reg_match_post(), rb_reg_match_pre(), rb_reg_nth_defined(), and rb_reg_nth_match().