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When can I use a forward declaration?
I am looking for the definition of when I am allowed to do forward declaration of a class in another class's header file:
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Does Python support short-circuiting?
Does Python support short-circuiting in boolean expressions?
3 Answers
3
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Combining “LIKE” and “IN” for SQL Server [duplicate]
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Effectively, the IN statement creates a series of OR statements... so
SELECT * FROM table WHERE column IN (1, 2, 3)
Is effectively
SELECT * FROM table WHERE column = 1 OR column = 2 OR column = 3
And sadly, that is the route you'll have to take with your LIKE statement...
What is a magic number, and why is it bad? [closed]
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A magic number is a direct usage of a number in the code.
For example, if you have (in Java):
public class Foo {
public void setPassword(String password) {
// don't do this
if (password.length() > 7) {
throw new InvalidArgumentException("passwo...
How can I check if a string is null or empty in PowerShell?
Is there a built-in IsNullOrEmpty -like function in order to check if a string is null or empty, in PowerShell?
11 Answers...
What is the strict aliasing rule?
When asking about common undefined behavior in C , people sometimes refer to the strict aliasing rule.
What are they talking about?
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Programmatically Lighten or Darken a hex color (or rgb, and blend colors)
Here is a function I was working on to programmatically lighten or darken a hex color by a specific amount. Just pass in a string like "3F6D2A" for the color ( col ) and a base10 integer ( amt ) for the amount to lighten or darken. To darken, pass in a negative number (i.e. -20 ).
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403 Forbidden vs 401 Unauthorized HTTP responses
For a web page that exists, but for which a user does not have sufficient privileges (they are not logged in or do not belong to the proper user group), what is the proper HTTP response to serve?
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PHP parse/syntax errors; and how to solve them
Everyone runs into syntax errors. Even experienced programmers make typos. For newcomers, it's just part of the learning process. However, it's often easy to interpret error messages such as:
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How to know user has clicked “X” or the “Close” button?
... CloseReason.UserClosing to know that the user had decided to close the form
but I guess it is the same for both clicking the X button or clicking the close button.
So how can I differentiate between these two in my code?
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