rhash.h File Reference

(e45f082e39924a0cd0644a1287ae2391df7321d2)

Routines to manipulate struct RHash. More...

#include "ruby/internal/config.h"
#include "ruby/internal/dllexport.h"
#include "ruby/internal/value.h"
#include "ruby/backward.h"

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Macros
#define	RHASH_IFNONE(h)   rb_hash_ifnone(h)
#define	RHASH_SIZE(h)   rb_hash_size_num(h)
	Queries the size of the hash.
#define	RHASH_EMPTY_P(h)   (RHASH_SIZE(h) == 0)
	Checks if the hash is empty.
#define	RHASH_SET_IFNONE(h, ifnone)   rb_hash_set_ifnone((VALUE)h, ifnone)
	Destructively updates the default value of the hash.

Functions
size_t	rb_hash_size_num (VALUE hash)
	This is the implementation detail of RHASH_SIZE.
struct st_table *	rb_hash_tbl (VALUE hash)
	This is the implementation detail of RHASH_TBL.
static st_table *	RHASH_TBL (VALUE h)
	Retrieves the internal table.
VALUE	rb_hash_set_ifnone (VALUE hash, VALUE ifnone)
	This is the implementation detail of RHASH_SET_IFNONE.

Detailed Description

Routines to manipulate struct RHash.

Author

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

The struct RHash itself is opaque.

Definition in file rhash.h.

Macro Definition Documentation

RHASH_EMPTY_P

#define RHASH_EMPTY_P

(

h

)

(RHASH_SIZE(h) == 0)

Checks if the hash is empty.

Parameters

[in]

h

An instance of RHash.

Precondition

h must be of RUBY_T_HASH.

Return values

true	It is.
false	It isn't.

Definition at line 67 of file rhash.h.

RHASH_IFNONE

#define RHASH_IFNONE

(

h

)

rb_hash_ifnone(h)

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.

Definition at line 47 of file rhash.h.

RHASH_SET_IFNONE

#define RHASH_SET_IFNONE	(		h,
			ifnone
	)		rb_hash_set_ifnone((VALUE)h, ifnone)

Destructively updates the default value of the hash.

Parameters

[out]	h	An instance of RHash.
[in]	ifnone	Arbitrary default value.

Precondition

h must be of RUBY_T_HASH.

Definition at line 80 of file rhash.h.

RHASH_SIZE

#define RHASH_SIZE

(

h

)

rb_hash_size_num(h)

Queries the size of the hash.

Size here means the number of keys that the hash stores.

Parameters

[in]

h

An instance of RHash.

Precondition

h must be of RUBY_T_HASH.

Returns

The size of the hash.

Definition at line 57 of file rhash.h.

Function Documentation

rb_hash_set_ifnone()

VALUE rb_hash_set_ifnone	(	VALUE	hash,
		VALUE	ifnone
	)

This is the implementation detail of RHASH_SET_IFNONE.

People don't call this directly.

Parameters

[out]	hash	An instance of RHash.
[in]	ifnone	Arbitrary default value.

Precondition

hash must be of RUBY_T_HASH.

Definition at line 133 of file hash.c.

rb_hash_size_num()

size_t rb_hash_size_num

(

VALUE

hash

)

This is the implementation detail of RHASH_SIZE.

People don't call this directly.

Parameters

[in]

hash

An instance of RHash.

Precondition

hash must be of RUBY_T_HASH.

Returns

The size of the hash.

Definition at line 3265 of file hash.c.

rb_hash_tbl()

struct st_table * rb_hash_tbl

(

VALUE

hash

)

This is the implementation detail of RHASH_TBL.

People don't call this directly.

Parameters

[in]	hash	An instance of RHash.
[in]	file	The __FILE__.
[in]	line	The __LINE__.

Precondition

hash must be of RUBY_T_HASH.

Returns

Table that has the contents of the hash.

Definition at line 1804 of file hash.c.

Referenced by RHASH_TBL().

RHASH_TBL()

static st_table * RHASH_TBL ( VALUE  h )

inlinestatic

Retrieves the internal table.

Parameters

[in]

h

An instance of RHash.

Precondition

h must be of RUBY_T_HASH.

Returns

A struct st_table which has the contents of this hash.

Note

Nowadays as Ruby evolved over ages, RHash has multiple backend storage engines. h's backend is not guaranteed to be a st_table. This function creates one when necessary.

Deprecated:

This imposes that RHash can backed by a struct st_table which is limiting runtime optimizations.

Definition at line 122 of file rhash.h.