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What is the purpose of the word 'self'?

... But in __init__(self) method, it accepts self, then even without creating the object, how does it refer to itself? – saurav Jan 28 '18 at 10:10 ...
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How do you round to 1 decimal place in Javascript?

...) You might want to create a function for this: function roundedToFixed(_float, _digits){ var rounded = Math.pow(10, _digits); return (Math.round(_float * rounded) / rounded).toFixed(_digits); } share | ...
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PHP abstract properties

...cks (say, in the constructor) for the $tablename variable, e.g.: class Foo_Abstract { public final function __construct(/*whatever*/) { if(!isset($this->tablename)) throw new LogicException(get_class($this) . ' must have a $tablename'); } } To enforce this for all derived classes...
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Get the full URL in PHP

... Have a look at $_SERVER['REQUEST_URI'], i.e. $actual_link = "http://$_SERVER[HTTP_HOST]$_SERVER[REQUEST_URI]"; (Note that the double quoted string syntax is perfectly correct) If you want to support both HTTP and HTTPS, you can use $act...
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Allowed characters in Linux environment variable names

...EE Std 1003.1-2001 consist solely of uppercase letters, digits, and the '_' (underscore) from the characters defined in Portable Character Set and do not begin with a digit. Other characters may be permitted by an implementation; applications shall tolerate the presence of such names. ...
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Extending the User model with custom fields in Django

...o.contrib.auth.models import User from django.db.models.signals import post_save class UserProfile(models.Model): user = models.OneToOneField(User) #other fields here def __str__(self): return "%s's profile" % self.user def create_user_profile(sender, instance, creat...
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Android Studio installation on Windows 7 fails, no JDK found

... Adding a system variable JDK_HOME with value c:\Program Files\Java\jdk1.7.0_21\ worked for me. The latest Java release can be downloaded here. Additionally, make sure the variable JAVA_HOME is also set with the above location. ...
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What does the slash mean in help() output?

...meters could only be specified in the C API. It means the key argument to __contains__ can only be passed in by position (range(5).__contains__(3)), not as a keyword argument (range(5).__contains__(key=3)), something you can do with positional arguments in pure-python functions. Also see the Argum...
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What happens to global and static variables in a shared library when it is dynamically linked?

...yntax similar to the function export/import syntax, i.e.: #ifdef COMPILING_THE_DLL #define MY_DLL_EXPORT extern "C" __declspec(dllexport) #else #define MY_DLL_EXPORT extern "C" __declspec(dllimport) #endif MY_DLL_EXPORT int my_global; When you do that, the global variable is added to the list of...
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Why do we always prefer using parameters in SQL statements?

... the SQL statement is not going to be the same – marc_s Sep 21 '11 at 20:57 1 that means sql inje...