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Why is using 'eval' a bad practice?
...d eval have nothing to do with each other. An application that's fundamentally mis-designed is fundamentally mis-designed. eval is no more the root cause of bad design than division by zero or attempting to import a module which is known not to exist. eval isn't insecure. Applications are insecu...
Constants in Objective-C
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Overall, great answer, with one glaring caveat: you DO NOT want to test for string equality with the == operator in Objective-C, since it tests memory address. Always use -isEqualToString: for this. You can easily get a different...
How to remove all of the data in a table using Django
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Inside a manager:
def delete_everything(self):
Reporter.objects.all().delete()
def drop_table(self):
cursor = connection.cursor()
table_name = self.model._meta.db_table
sql = "DROP TABLE %s;" % (table_name, )
cursor.execute(sql)
...
How to set Oracle's Java as the default Java in Ubuntu?
...of the JVM, you don't need to update your .bashrc file, it should automatically point to the new version.
If you want to set JAVA_HOME environment variables globally and at system level means use should set in /etc/environment file.
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Getting a list of all subdirectories in the current directory
Is there a way to return a list of all the subdirectories in the current directory in Python?
27 Answers
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What exactly does Perl's “bless” do?
...to a hash (most common case), to an array (not so common), to a scalar (usually this indicates an inside-out object), to a regular expression, subroutine or TYPEGLOB (see the book Object Oriented Perl: A Comprehensive Guide to Concepts and Programming Techniques by Damian Conway for useful examples)...
Parse query string in JavaScript [duplicate]
...ne query value. I think a better abstraction is to return a JS object with all the name value pairs from the query string
– Juan Mendes
Sep 4 '12 at 23:37
11
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Best approach to converting Boolean object to string in java
...irst test for null and later invoke toString() method on your object.
Calling Boolean.toString(b) will invoke
public static String toString(boolean b) {
return b ? "true" : "false";
}
which is little slower than b.toString() since JVM needs to first unbox Boolean to boolean which will be...
What is an application binary interface (ABI)?
...but the API does not, then the old and new library versions are sometimes called "source compatible". This implies that while a program compiled for one library version will not work with the other, source code written for one will work for the other if re-compiled.
For this reason, developers ten...
How to declare an array in Python?
... should never refer to anything other than a list", since Python is dynamically typed.
*The default built-in Python type is called a list, not an array. It is an ordered container of arbitrary length that can hold a heterogenous collection of objects (their types do not matter and can be freely m...