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“Notice: Undefined variable”, “Notice: Undefined index”, and “Notice: Undefined offset” using PHP
...uses the same variable name. It is also a major security risk with register_globals turned on. E_NOTICE level error is issued in case of working with uninitialized variables, however not in the case of appending elements to the uninitialized array. isset() language construct can be used to detect if...
When should iteritems() be used instead of items()?
... more like a set (which you'd expect from a dict).
Simple example:
common_keys = list(dict_a.viewkeys() & dict_b.viewkeys())
Will give you a list of the common keys, but again, in Python 3.x - just use .keys() instead.
Python 3.x has generally been made to be more "lazy" - i.e. map is now e...
How do I calculate the date in JavaScript three months prior to today?
...tedMonth) {
result.setDate(0);
}
return result;
}
var dt2004_05_31 = new Date("2004-05-31 0:00"),
dt2001_05_31 = new Date("2001-05-31 0:00"),
dt2001_03_31 = new Date("2001-03-31 0:00"),
dt2001_02_28 = new Date("2001-02-28 0:00"),
result = addMonths(dt2001_05_31, -2...
Flattening a shallow list in Python [duplicate]
...ndexable sequence, consider itertools.chain and company.
>>> list_of_menuitems = [['image00', 'image01'], ['image10'], []]
>>> import itertools
>>> chain = itertools.chain(*list_of_menuitems)
>>> print(list(chain))
['image00', 'image01', 'image10']
It will work...
Python threading.timer - repeat function every 'n' seconds
...our timer thread you'd code the following
class MyThread(Thread):
def __init__(self, event):
Thread.__init__(self)
self.stopped = event
def run(self):
while not self.stopped.wait(0.5):
print("my thread")
# call a function
In the code that s...
What is SYSNAME data type in SQL Server?
...stored procedures etc within SQL Server.
For example, by executing Exec sp_help 'sys.tables' you will see that the column name is defined as sysname this is because the value of this is actually an object in itself (a table)
I would worry too much about it.
It's also worth noting that for those p...
How do I print the type or class of a variable in Swift?
...y<String>.self)")
Which outputs:
String(myvar0.dynamicType) -> __NSCFConstantString
String(myvar1.dynamicType) -> PureSwiftClass
String(myvar2.dynamicType) -> Int
String(myvar3.dynamicType) -> String
String(Int.self) -> Int
String((Int?).self -> Optional&...
How to manage local vs production settings in Django?
...
In settings.py:
try:
from local_settings import *
except ImportError as e:
pass
You can override what needed in local_settings.py; it should stay out of your version control then. But since you mention copying I'm guessing you use none ;)
...
What is the advantage of GCC's __builtin_expect in if else statements?
I came across a #define in which they use __builtin_expect .
6 Answers
6
...
Why does ReSharper tell me “implicitly captured closure”?
...r generates a type looks like :
[CompilerGenerated]
private sealed class c__DisplayClass2
{
public object x;
public ValueStore store;
public c__DisplayClass2()
{
base.ctor();
}
//Represents the first lambda expression: () => store.SetValue(x)
public void Capturedb__0()
{
...