How to use complex object as keys in associative arrays in PHP?

I would like to get values for a collection of values:

>>> class Foo() {}

>>> $v = (object)[42];



>>> $a = [1, 1, 2, 3, 5, Foo::class, 'o_o', $v]

>>> $b = [1, 1, 2, 3, 5, Foo::class, 'o_o', $v]



>>> $data[$a] = 42;

>>> echo $data[$b]

42

I tried with SplObjectStorage, but I need to convert $a into an object and in this case $a != $b because they are different instances:

$s = new SplObjectStorage()

$s[$a] = 42

echo $s[$b]

UnexpectedValueException with message 'Object not found'

How can I achieve this in PHP?

In Python I would have used:

>>> a = (1, 1, 2, 3, 5, Foo, 'o_o', hashable_object)

>>> b = (1, 1, 2, 3, 5, Foo, 'o_o', hashable_object)    

>>> data[a] = 42

>>> print(data[b])

42

EDIT

One not very efficient working solution would be:

>>> class Foo() {}

>>> $v = (object)[42];



>>> $a = [1, 1, 2, 3, 5, Foo::class, 'o_o', $v]

>>> $b = [1, 1, 2, 3, 5, Foo::class, 'o_o', $v]



>>> $data[serialize($a)] = 42;

>>> echo $data[serialize($b)]

42

edited Nov 25 '18 at 13:29

asked Nov 25 '18 at 13:21

nowox

6,208932102

That because the $a and $b are not the same (notice that $a !== $b as you mention) - so they not represent same key on the SplObjectStorage - so I guess it is the expected output

– dWinder
Nov 25 '18 at 13:45

Indeed, it is the expected output, but I don't know how to answer the question though.

– nowox
Nov 25 '18 at 13:45

Why do you think it is not efficient?

– revo
Nov 25 '18 at 15:10

add a comment |

I would like to get values for a collection of values:

>>> class Foo() {}

>>> $v = (object)[42];



>>> $a = [1, 1, 2, 3, 5, Foo::class, 'o_o', $v]

>>> $b = [1, 1, 2, 3, 5, Foo::class, 'o_o', $v]



>>> $data[$a] = 42;

>>> echo $data[$b]

42

I tried with SplObjectStorage, but I need to convert $a into an object and in this case $a != $b because they are different instances:

$s = new SplObjectStorage()

$s[$a] = 42

echo $s[$b]

UnexpectedValueException with message 'Object not found'

How can I achieve this in PHP?

In Python I would have used:

>>> a = (1, 1, 2, 3, 5, Foo, 'o_o', hashable_object)

>>> b = (1, 1, 2, 3, 5, Foo, 'o_o', hashable_object)    

>>> data[a] = 42

>>> print(data[b])

42

EDIT

One not very efficient working solution would be:

>>> class Foo() {}

>>> $v = (object)[42];



>>> $a = [1, 1, 2, 3, 5, Foo::class, 'o_o', $v]

>>> $b = [1, 1, 2, 3, 5, Foo::class, 'o_o', $v]



>>> $data[serialize($a)] = 42;

>>> echo $data[serialize($b)]

42

edited Nov 25 '18 at 13:29

asked Nov 25 '18 at 13:21

nowox

6,208932102

That because the $a and $b are not the same (notice that $a !== $b as you mention) - so they not represent same key on the SplObjectStorage - so I guess it is the expected output

– dWinder
Nov 25 '18 at 13:45

Indeed, it is the expected output, but I don't know how to answer the question though.

– nowox
Nov 25 '18 at 13:45

Why do you think it is not efficient?

– revo
Nov 25 '18 at 15:10

add a comment |

I would like to get values for a collection of values:

>>> class Foo() {}

>>> $v = (object)[42];



>>> $a = [1, 1, 2, 3, 5, Foo::class, 'o_o', $v]

>>> $b = [1, 1, 2, 3, 5, Foo::class, 'o_o', $v]



>>> $data[$a] = 42;

>>> echo $data[$b]

42

I tried with SplObjectStorage, but I need to convert $a into an object and in this case $a != $b because they are different instances:

$s = new SplObjectStorage()

$s[$a] = 42

echo $s[$b]

UnexpectedValueException with message 'Object not found'

How can I achieve this in PHP?

In Python I would have used:

>>> a = (1, 1, 2, 3, 5, Foo, 'o_o', hashable_object)

>>> b = (1, 1, 2, 3, 5, Foo, 'o_o', hashable_object)    

>>> data[a] = 42

>>> print(data[b])

42

EDIT

One not very efficient working solution would be:

>>> class Foo() {}

>>> $v = (object)[42];



>>> $a = [1, 1, 2, 3, 5, Foo::class, 'o_o', $v]

>>> $b = [1, 1, 2, 3, 5, Foo::class, 'o_o', $v]



>>> $data[serialize($a)] = 42;

>>> echo $data[serialize($b)]

42

edited Nov 25 '18 at 13:29

asked Nov 25 '18 at 13:21

nowox

6,208932102

I would like to get values for a collection of values:

>>> class Foo() {}

>>> $v = (object)[42];



>>> $a = [1, 1, 2, 3, 5, Foo::class, 'o_o', $v]

>>> $b = [1, 1, 2, 3, 5, Foo::class, 'o_o', $v]



>>> $data[$a] = 42;

>>> echo $data[$b]

42

I tried with SplObjectStorage, but I need to convert $a into an object and in this case $a != $b because they are different instances:

$s = new SplObjectStorage()

$s[$a] = 42

echo $s[$b]

UnexpectedValueException with message 'Object not found'

How can I achieve this in PHP?

In Python I would have used:

>>> a = (1, 1, 2, 3, 5, Foo, 'o_o', hashable_object)

>>> b = (1, 1, 2, 3, 5, Foo, 'o_o', hashable_object)    

>>> data[a] = 42

>>> print(data[b])

42

EDIT

One not very efficient working solution would be:

>>> class Foo() {}

>>> $v = (object)[42];



>>> $a = [1, 1, 2, 3, 5, Foo::class, 'o_o', $v]

>>> $b = [1, 1, 2, 3, 5, Foo::class, 'o_o', $v]



>>> $data[serialize($a)] = 42;

>>> echo $data[serialize($b)]

42

php associative-array

edited Nov 25 '18 at 13:29

asked Nov 25 '18 at 13:21

nowox

6,208932102

edited Nov 25 '18 at 13:29

asked Nov 25 '18 at 13:21

nowox

6,208932102

edited Nov 25 '18 at 13:29

asked Nov 25 '18 at 13:21

nowox

6,208932102

asked Nov 25 '18 at 13:21

nowox

6,208932102

asked Nov 25 '18 at 13:21

nowox

6,208932102

That because the $a and $b are not the same (notice that $a !== $b as you mention) - so they not represent same key on the SplObjectStorage - so I guess it is the expected output

– dWinder
Nov 25 '18 at 13:45

Indeed, it is the expected output, but I don't know how to answer the question though.

– nowox
Nov 25 '18 at 13:45

Why do you think it is not efficient?

– revo
Nov 25 '18 at 15:10

add a comment |

That because the $a and $b are not the same (notice that $a !== $b as you mention) - so they not represent same key on the SplObjectStorage - so I guess it is the expected output

– dWinder
Nov 25 '18 at 13:45

Indeed, it is the expected output, but I don't know how to answer the question though.

– nowox
Nov 25 '18 at 13:45

Why do you think it is not efficient?

– revo
Nov 25 '18 at 15:10

That because the $a and $b are not the same (notice that $a !== $b as you mention) - so they not represent same key on the SplObjectStorage - so I guess it is the expected output

– dWinder
Nov 25 '18 at 13:45

Indeed, it is the expected output, but I don't know how to answer the question though.

– nowox
Nov 25 '18 at 13:45

Why do you think it is not efficient?

– revo
Nov 25 '18 at 15:10

add a comment |

2 Answers
2

active

oldest

votes

According to php manual arrays and objects cannot be used as array keys.

What you could do is this:

>>> class Foo {}

>>> $test = new stdClass();

>>> $test->{implode([1, 1, 2, 3, 5, Foo::class, 'o_o'])} = 42;

>>> $test->{implode([1, 1, 2, 3, 5, Foo::class, 'o_o'])};

=> 42

What i was going to do is this:

$test->something = [ 42 => [1, 1, 2, 3, 5, Foo::class, 'o_o']];

array_search([1, 1, 2, 3, 5, Foo::class, 'o_o'], $test->something, true);

=> 42

I hope it helps.

answered Nov 25 '18 at 13:56

Vaggelis Ksps

19119

Not sure it is more efficient than using serialize

– nowox
Nov 25 '18 at 13:57

1

According @Peon 's comment here Implode 2 elements: 1.8937180042267 seconds, Implode 4 elements: 2.4380650520325 seconds, Implode 8 elements: 3.6058769226074 seconds Not exactly two times, but close to it, while serialize changes with the same progression type, but slower rate. So i think serialize is faster and it is up to you man and always add the full path of the function for better performance. For example array_search()

– Vaggelis Ksps
Nov 25 '18 at 14:05

add a comment |

By looking at the PHP doc I found 'DsMap' available from PECL. With this you can write:

$map = new DsMap();



$v = (object)[41];



$a = [1, 1, 2, 3, 5, 'o_o', $v];

$b = [1, 1, 2, 3, 5, 'o_o', $v];



$map[$a] = 42;



var_dump($map[$b]);

I also looked at the implementation:

https://github.com/php-ds/ext-ds/blob/master/src/ds/ds_htable.c

The zval is hashed with this function

static uint32_t get_array_hash(zval *array)

{

    uint32_t                   hash;

    php_serialize_data_t       var_hash;

    smart_str                  buffer = {0};



    PHP_VAR_SERIALIZE_INIT(var_hash);

    php_var_serialize(&buffer, array, &var_hash);

    PHP_VAR_SERIALIZE_DESTROY(var_hash);



    smart_str_0(&buffer);



    if (buffer.s) {

        hash = get_string_hash(buffer.s);

        zend_string_free(buffer.s);

    } else {

        hash = 0;

    }



    return hash;

}

So behind the scene it is the serialize function that is used. I feel a bit sad about this. So your inefficient function will be not much inefficient at the end.

answered Nov 25 '18 at 17:59

nowox

6,208932102

add a comment |

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2 Answers
2

active

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votes

2 Answers
2

active

oldest

votes

According to php manual arrays and objects cannot be used as array keys.

What you could do is this:

>>> class Foo {}

>>> $test = new stdClass();

>>> $test->{implode([1, 1, 2, 3, 5, Foo::class, 'o_o'])} = 42;

>>> $test->{implode([1, 1, 2, 3, 5, Foo::class, 'o_o'])};

=> 42

What i was going to do is this:

$test->something = [ 42 => [1, 1, 2, 3, 5, Foo::class, 'o_o']];

array_search([1, 1, 2, 3, 5, Foo::class, 'o_o'], $test->something, true);

=> 42

I hope it helps.

answered Nov 25 '18 at 13:56

Vaggelis Ksps

19119

Not sure it is more efficient than using serialize

– nowox
Nov 25 '18 at 13:57

1

According @Peon 's comment here Implode 2 elements: 1.8937180042267 seconds, Implode 4 elements: 2.4380650520325 seconds, Implode 8 elements: 3.6058769226074 seconds Not exactly two times, but close to it, while serialize changes with the same progression type, but slower rate. So i think serialize is faster and it is up to you man and always add the full path of the function for better performance. For example array_search()

– Vaggelis Ksps
Nov 25 '18 at 14:05

add a comment |

According to php manual arrays and objects cannot be used as array keys.

What you could do is this:

>>> class Foo {}

>>> $test = new stdClass();

>>> $test->{implode([1, 1, 2, 3, 5, Foo::class, 'o_o'])} = 42;

>>> $test->{implode([1, 1, 2, 3, 5, Foo::class, 'o_o'])};

=> 42

What i was going to do is this:

$test->something = [ 42 => [1, 1, 2, 3, 5, Foo::class, 'o_o']];

array_search([1, 1, 2, 3, 5, Foo::class, 'o_o'], $test->something, true);

=> 42

I hope it helps.

answered Nov 25 '18 at 13:56

Vaggelis Ksps

19119

Not sure it is more efficient than using serialize

– nowox
Nov 25 '18 at 13:57

1

According @Peon 's comment here Implode 2 elements: 1.8937180042267 seconds, Implode 4 elements: 2.4380650520325 seconds, Implode 8 elements: 3.6058769226074 seconds Not exactly two times, but close to it, while serialize changes with the same progression type, but slower rate. So i think serialize is faster and it is up to you man and always add the full path of the function for better performance. For example array_search()

– Vaggelis Ksps
Nov 25 '18 at 14:05

add a comment |

According to php manual arrays and objects cannot be used as array keys.

What you could do is this:

>>> class Foo {}

>>> $test = new stdClass();

>>> $test->{implode([1, 1, 2, 3, 5, Foo::class, 'o_o'])} = 42;

>>> $test->{implode([1, 1, 2, 3, 5, Foo::class, 'o_o'])};

=> 42

What i was going to do is this:

$test->something = [ 42 => [1, 1, 2, 3, 5, Foo::class, 'o_o']];

array_search([1, 1, 2, 3, 5, Foo::class, 'o_o'], $test->something, true);

=> 42

I hope it helps.

answered Nov 25 '18 at 13:56

Vaggelis Ksps

19119

According to php manual arrays and objects cannot be used as array keys.

What you could do is this:

>>> class Foo {}

>>> $test = new stdClass();

>>> $test->{implode([1, 1, 2, 3, 5, Foo::class, 'o_o'])} = 42;

>>> $test->{implode([1, 1, 2, 3, 5, Foo::class, 'o_o'])};

=> 42

What i was going to do is this:

$test->something = [ 42 => [1, 1, 2, 3, 5, Foo::class, 'o_o']];

array_search([1, 1, 2, 3, 5, Foo::class, 'o_o'], $test->something, true);

=> 42

I hope it helps.

answered Nov 25 '18 at 13:56

Vaggelis Ksps

19119

answered Nov 25 '18 at 13:56

Vaggelis Ksps

19119

answered Nov 25 '18 at 13:56

Vaggelis Ksps

19119

answered Nov 25 '18 at 13:56

Vaggelis Ksps

19119

Not sure it is more efficient than using serialize

– nowox
Nov 25 '18 at 13:57

1

According @Peon 's comment here Implode 2 elements: 1.8937180042267 seconds, Implode 4 elements: 2.4380650520325 seconds, Implode 8 elements: 3.6058769226074 seconds Not exactly two times, but close to it, while serialize changes with the same progression type, but slower rate. So i think serialize is faster and it is up to you man and always add the full path of the function for better performance. For example array_search()

– Vaggelis Ksps
Nov 25 '18 at 14:05

add a comment |

Not sure it is more efficient than using serialize

– nowox
Nov 25 '18 at 13:57

1

According @Peon 's comment here Implode 2 elements: 1.8937180042267 seconds, Implode 4 elements: 2.4380650520325 seconds, Implode 8 elements: 3.6058769226074 seconds Not exactly two times, but close to it, while serialize changes with the same progression type, but slower rate. So i think serialize is faster and it is up to you man and always add the full path of the function for better performance. For example array_search()

– Vaggelis Ksps
Nov 25 '18 at 14:05

Not sure it is more efficient than using serialize

– nowox
Nov 25 '18 at 13:57

According @Peon 's comment here Implode 2 elements: 1.8937180042267 seconds, Implode 4 elements: 2.4380650520325 seconds, Implode 8 elements: 3.6058769226074 seconds Not exactly two times, but close to it, while serialize changes with the same progression type, but slower rate. So i think serialize is faster and it is up to you man and always add the full path of the function for better performance. For example array_search()

– Vaggelis Ksps
Nov 25 '18 at 14:05

add a comment |

By looking at the PHP doc I found 'DsMap' available from PECL. With this you can write:

$map = new DsMap();



$v = (object)[41];



$a = [1, 1, 2, 3, 5, 'o_o', $v];

$b = [1, 1, 2, 3, 5, 'o_o', $v];



$map[$a] = 42;



var_dump($map[$b]);

I also looked at the implementation:

https://github.com/php-ds/ext-ds/blob/master/src/ds/ds_htable.c

The zval is hashed with this function

static uint32_t get_array_hash(zval *array)

{

    uint32_t                   hash;

    php_serialize_data_t       var_hash;

    smart_str                  buffer = {0};



    PHP_VAR_SERIALIZE_INIT(var_hash);

    php_var_serialize(&buffer, array, &var_hash);

    PHP_VAR_SERIALIZE_DESTROY(var_hash);



    smart_str_0(&buffer);



    if (buffer.s) {

        hash = get_string_hash(buffer.s);

        zend_string_free(buffer.s);

    } else {

        hash = 0;

    }



    return hash;

}

So behind the scene it is the serialize function that is used. I feel a bit sad about this. So your inefficient function will be not much inefficient at the end.

answered Nov 25 '18 at 17:59

nowox

6,208932102

add a comment |

By looking at the PHP doc I found 'DsMap' available from PECL. With this you can write:

$map = new DsMap();



$v = (object)[41];



$a = [1, 1, 2, 3, 5, 'o_o', $v];

$b = [1, 1, 2, 3, 5, 'o_o', $v];



$map[$a] = 42;



var_dump($map[$b]);

I also looked at the implementation:

https://github.com/php-ds/ext-ds/blob/master/src/ds/ds_htable.c

The zval is hashed with this function

static uint32_t get_array_hash(zval *array)

{

    uint32_t                   hash;

    php_serialize_data_t       var_hash;

    smart_str                  buffer = {0};



    PHP_VAR_SERIALIZE_INIT(var_hash);

    php_var_serialize(&buffer, array, &var_hash);

    PHP_VAR_SERIALIZE_DESTROY(var_hash);



    smart_str_0(&buffer);



    if (buffer.s) {

        hash = get_string_hash(buffer.s);

        zend_string_free(buffer.s);

    } else {

        hash = 0;

    }



    return hash;

}

So behind the scene it is the serialize function that is used. I feel a bit sad about this. So your inefficient function will be not much inefficient at the end.

answered Nov 25 '18 at 17:59

nowox

6,208932102

add a comment |

By looking at the PHP doc I found 'DsMap' available from PECL. With this you can write:

$map = new DsMap();



$v = (object)[41];



$a = [1, 1, 2, 3, 5, 'o_o', $v];

$b = [1, 1, 2, 3, 5, 'o_o', $v];



$map[$a] = 42;



var_dump($map[$b]);

I also looked at the implementation:

https://github.com/php-ds/ext-ds/blob/master/src/ds/ds_htable.c

The zval is hashed with this function

static uint32_t get_array_hash(zval *array)

{

    uint32_t                   hash;

    php_serialize_data_t       var_hash;

    smart_str                  buffer = {0};



    PHP_VAR_SERIALIZE_INIT(var_hash);

    php_var_serialize(&buffer, array, &var_hash);

    PHP_VAR_SERIALIZE_DESTROY(var_hash);



    smart_str_0(&buffer);



    if (buffer.s) {

        hash = get_string_hash(buffer.s);

        zend_string_free(buffer.s);

    } else {

        hash = 0;

    }



    return hash;

}

So behind the scene it is the serialize function that is used. I feel a bit sad about this. So your inefficient function will be not much inefficient at the end.

answered Nov 25 '18 at 17:59

nowox

6,208932102

By looking at the PHP doc I found 'DsMap' available from PECL. With this you can write:

$map = new DsMap();



$v = (object)[41];



$a = [1, 1, 2, 3, 5, 'o_o', $v];

$b = [1, 1, 2, 3, 5, 'o_o', $v];



$map[$a] = 42;



var_dump($map[$b]);

I also looked at the implementation:

https://github.com/php-ds/ext-ds/blob/master/src/ds/ds_htable.c

The zval is hashed with this function

static uint32_t get_array_hash(zval *array)

{

    uint32_t                   hash;

    php_serialize_data_t       var_hash;

    smart_str                  buffer = {0};



    PHP_VAR_SERIALIZE_INIT(var_hash);

    php_var_serialize(&buffer, array, &var_hash);

    PHP_VAR_SERIALIZE_DESTROY(var_hash);



    smart_str_0(&buffer);



    if (buffer.s) {

        hash = get_string_hash(buffer.s);

        zend_string_free(buffer.s);

    } else {

        hash = 0;

    }



    return hash;

}

So behind the scene it is the serialize function that is used. I feel a bit sad about this. So your inefficient function will be not much inefficient at the end.

answered Nov 25 '18 at 17:59

nowox

6,208932102

answered Nov 25 '18 at 17:59

nowox

6,208932102

answered Nov 25 '18 at 17:59

nowox

6,208932102

answered Nov 25 '18 at 17:59

nowox

6,208932102

add a comment |

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