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Why doesn't 'ref' and 'out' support polymorphism?
...pass a variable of type Animal to N?
Hmm.
Well, why not? N cannot read from n, it can only write to it, right? You write a Tiger to a variable of type Animal and you're all set, right?
Wrong. The rule is not "N can only write to n".
The rules are, briefly:
1) N has to write to n before N ...
Why does the C++ map type argument require an empty constructor when using []?
...
This issue comes with operator[]. Quote from SGI documentation:
data_type& operator[](const key_type& k) - Returns a reference to the object
that is associated with a particular
key. If the map does not already
contain such an object, operator[]...
Which cryptographic hash function should I choose?
.... Even though there are no known pre-image attacks to date on MD5 the line from the security experts is that MD5 should not be used where you need to defend against pre-image attacks. SAME goes for SHA1.
Keep in mind, not all algorithms need to defend against pre-image or collision attacks. Take t...
Do you need text/javascript specified in your tags?
...the <!-- //--> hack with scripts. It was intended to prevent scripts from showing up as text on the first generation browsers Netscape 1 and Mosaic. It has not been necessary for many years. <!-- //--> is supposed to signal an HTML comment. Comments should be ignored, not compiled and ex...
Two inline-block, width 50% elements wrap to second line [duplicate]
... below will solve your IE7 woes, and wont require you to remove whitespace from your HTML, which is a pain, and hard to eradicate from dynamic situations without a post-processor which costs more CPU-time for marginal bandwidth savings.
– Phil Ricketts
Jul 24 '...
access denied for load data infile in MySQL
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@Stewart, please remove 'local' from the above command. Later mysql versions do not seem to support this flag when global variable 'local_infile' variable is set to 'ON' (as below). The command will therefore, be; mysql> load data infile 'home/data.txt'...
Iterating Over Dictionary Key Values Corresponding to List in Python
... to iterate over their items. Also, with pattern matching and the division from __future__ you can do simplify things a bit.
Finally, you can separate your logic from your printing to make things a bit easier to refactor/debug later.
from __future__ import division
def Pythag(league):
def win...
SQL function as default parameter value?
...
I infer you're using Microsoft SQL Server from the square brackets in your example.
From MSDN:
Only a constant value, such as a
character string; a scalar function
(either a system, user-defined, or CLR
function); or NULL can be used as a
default.
The ...
What should I do if the current ASP.NET session is null?
...Page. So if you are calling other functionality, including static classes, from your page, you should be fine.
If you have some classes doing initialization logic during startup, for example on the Application_Start event or by using a static constructor, Session state might not be available. It all...
Check that Field Exists with MongoDB
...ents, you won't even see the difference. And if you were to run this query from external driver, I'm pretty sure most of them shield you from the cursor implementation detail.
– Sergio Tulentsev
Feb 3 '16 at 6:36
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