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Questions tagged [unset]

Removing the value associated with a variable or property from the current environment.

Common usages:

  • Destroying a variable or member of an array in PHP.
  • Removing the value bound to a property in Apache Ant.
  • Removing a variable from the environment of a shell script.
595 questions
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25 answers

Deleting an element from an array in PHP

Is there an easy way to delete an element from an array using PHP, such that foreach ($array) no longer includes that element? I thought that setting it to null would do it, but apparently it does not work.
Ben
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How can I remove a key from a Python dictionary?

I want to remove a key from a dictionary if it is present. I currently use this code: if key in my_dict: del my_dict[key] Without the if statement, the code will raise KeyError if the key is not present. How can I handle this more simply? See…
Tony
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7 answers

How do I delete an exported environment variable?

Before installing gnuplot, I set the environment variable GNUPLOT_DRIVER_DIR = /home/gnuplot/build/src. During the installation, something went wrong. I want to remove the GNUPLOT_DRIVER_DIR environment variable. How can I achieve it?
A. K.
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12 answers

How can I unset a JavaScript variable?

I have a global variable in JavaScript (actually a window property, but I don't think it matters) which was already populated by a previous script, but I don't want another script that will run later to see its value or that it was even…
Guss
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6 answers

How to delete object from array inside foreach loop?

I iterate through an array of objects and want to delete one of the objects based on it's 'id' property, but my code doesn't work. foreach($array as $element) { foreach($element as $key => $value) { if($key == 'id' && $value ==…
ababa
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16 answers

Unset readonly variable in bash

How do I unset a readonly variable in Bash? $ readonly PI=3.14 $ unset PI bash: PI: readonly variable or is it not possible?
Kokizzu
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9 answers

Unsetting array values in a foreach loop

I have a foreach loop set up to go through my array, check for a certain link, and if it finds it removes that link from the array. My code: foreach($images as $image) { if($image == 'http://i27.tinypic.com/29yk345.gif' || $image ==…
Matt
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3 answers

How to unset multiple variables?

Possible Duplicate: Can you unset() many variables at once in PHP? I have 3 variables var1 var2 var3. Is there's a way of un-setting them without repeated use of unset() function ?
Yousuf Memon
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How unset a lot of environment variables

Have any way to unset different variables using a one command? unset HTTP_PROXY unset HTTPS_PROXY unset FTP_PROXY unset ALL_PROXY unset NO_PROXY
Bruno Wego
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18 answers

Problems deleting cookies, won't unset

I've tried searching the php manual and internet on how to delete cookies and I've tried it the exact same way they all say: setcookie("name", '', 1); or setcookie("name", '', time()-3600); But when I check the cookies in the cookies dialog in…
GroovyPanda
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4 answers

delete all keys except one in dictionary

I have a dictionary lang = {'ar':'arabic', 'ur':'urdu','en':'english'} What I want to do is to delete all the keys except one key. Suppose I want to save only en here. How can I do it ? (pythonic solution) What I have tried: In [18]: for k in…
NIlesh Sharma
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6 answers

PHP Unset Array value effect on other indexes

I am working with a PHP loop, and I had one question regarding how unset affects the array keys. This array uses the standard numeric keys assigned by PHP, 0, 1, 2, 3 etc.... Whenever unset() runs on an array value, are the array keys shuffled or…
Oliver Spryn
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6 answers

Fatal error: Cannot unset string offsets error?

Not sure why this is occurring: Basically, I have an array that contains the following arrays, see var_dump: array(2) { [0]=> array(1) { [0]=> string(3) "ivr" } [1]=> array(1) { [0]=> string(9) "ivr_dests" } } Obviously this…
Jared
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Can you unset() many variables at once in PHP?

I have a pretty high traffic social network site, I would like to get into the habit of unsetting large array and mysql object and even some string variables. So is it possible to unset more then 1 item in PHP example:
JasonDavis
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Unset a row in a multidimensional array

I have this array $output which looks like this: Array( [0] => Array( [0] => 1a [1] => 1b [2] => 1c ) [1] => Array( [0] => 2a [1] => 2b [2] => 2c ) [2] => Array( [0] => 3a …
Giel
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