Language feature of PHP: A variable variable takes the value of a variable and treats that as the name of a variable.
Language feature of PHP: A variable variable takes the value of a variable and treats that as the name of a variable.
Questions tagged [variable-variables]
171 questions
541
votes
17 answers
How do I create variable variables?
I know that some other languages, such as PHP, support a concept of "variable variable names" - that is, the contents of a string can be used as part of a variable name.
I heard that this is a bad idea in general, but I think it would solve some…
Pyornide
126
votes
9 answers
"Variable" variables in JavaScript
I know it's possible in PHP to have "variable" variables. For example,
$x = "variable";
$$x = "Hello, World!";
echo $variable; // Displays "Hello, World!"
Is it possible to refer to a variable by its name as a string in JavaScript? How would it be…
ShoeLace1291
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votes
5 answers
How do I import variable packages in Python like using variable variables ($$) in PHP?
I want to import some package depending on which value the user chooses.
The default is file1.py:
from files import file1
If user chooses file2, it should be :
from files import file2
In PHP, I can do this using variable variables:
$file_name =…
skargor
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15
votes
5 answers
How can I select a variable by (string) name?
I want to return a pre-determined list from my function, based on the string input.
def get_ext(file_type):
text = ['txt', 'doc']
audio = ['mp3', 'wav']
video = ['mp4', 'mkv']
return # what do I return here?
get_ext('audio') …
Ludoloco
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14
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3 answers
what is "$$" in PHP
I saw this code
if (is_null($$textVarName)) {
$$textVarName = $_defaultTexts[$type];
}
what is code "$$" ?
meotimdihia
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12
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1 answer
How do I dynamically create the variable name in a PHP loop?
Ok so i have this php foreach loop
rows as $step) { ?>
and $step will be the step numbers 1, 2, 3, 4, 5 up to the total steps
within the loop i a need to set the value of the images within the loop to standard_image_1…
Matt Elhotiby
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9
votes
3 answers
java String to class
I have got a bean class named Bean1. In my main method I have got a string containing the name of the variable:
String str= "Bean1";
Now how can I use the String variable to get the class and access the Bean properties?
MANU SINHA
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9
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7 answers
What's an actual use of variable variables?
Variable variables seem pretty cool, but I can't think of a scenario where one would actually use them in a production environment. What would such a scenario be? How were they used?
user151841
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8
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7 answers
How to check if a string can be used as a variable name in PHP?
In PHP one can use variable variables...
For example...
class obj { }
$fieldName = "Surname";
$object = new obj();
$object->Name = "John";
$object->$fieldName = "Doe";
echo "{$object->Name} {$object->Surname}"; // This echoes "John Doe".
However,…
Kornelije Petak
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6
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2 answers
Is the dollar sign in a variable variable considered the dereference operator?
I was showing someone how you can create variable variable variables in PHP (I'd only recommend using them NEVER, it's horrible practice and you are a bad person if you use variable variable variables in actual production code), and they asked if…
Cyclone
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6
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4 answers
Variable variables handling order: changes in PHP 7
With the new PHP 7.0.0 out now, I'm a bit worried about the changes in evaluation order of the so-called 'variable variables'.
On this page, under 'Changes to variable handling', a table is displayed with examples of expressions with their handling…
Marten Koetsier
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6
votes
8 answers
Variable variable class extensions in PHP--is it possible?
Is something like the following possible in PHP?
$blah = 'foo1';
class foo2 extends $blah {
//...
}
class foo1 {
//...
}
This gives an error.
I want to dynamically set $blah so I can extend whatever class I want.
Edit: The reason for…
Darryl Hein
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6
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4 answers
Javascript's equivalent to PHP's $$varName
Possible Duplicate:
How to access javascript variable value by creating another variable via concatenation?
In PHP I can have:
$theVariable = "bigToe";
$bigToe = "is broken";
such that:
echo "my ".$theVariable." ".$$theVariable;
would…
Aaron Luman
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1 answer
variable-variables in PHP
I know you can do: $hash('foo') and $$foo and also $bar[$foo], what are each of these things called?
Johnny
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set variable variable as array key
I'm not sure how to ask this question, but here goes:
$id = 1;
$age = 2;
$sort = "id"; // or "age";
$arr = array($$sort => 'string'); // so that it becomes 1 => 'string'
^ what goes here? // instead of 'id' => string'
Is…
d-_-b
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