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Macro vs Function in C
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Macros are error-prone because they rely on textual substitution and do not perform type-checking. For example, this macro:
#define square(a) a * a
works fine when used with an integer:
square(5) --> 5 * 5 --> 25
but does very strange things when used with expressions:
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Visual Studio: How to break on handled exceptions?
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With a solution open, go to the Debug - Exceptions (Ctrl+D,E) menu option. From there you can choose to break on Thrown or User-unhandled exceptions.
EDIT: My instance is set up with the C# "profile" perhaps it isn't there f...
How to get file_get_contents() to work with HTTPS?
I'm working on setting up credit card processing and needed to use a workaround for CURL. The following code worked fine when I was using the test server (which wasn't calling an SSL URL), but now when I am testing it on the working server with HTTPS, it's failing with the error message "failed to o...
Is there a minlength validation attribute in HTML5?
It seems the minlength attribute for an <input> field doesn't work.
17 Answers
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ansible: lineinfile for several lines?
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You can use a loop to do it. Here's an example using a with_items loop:
- name: Set some kernel parameters
lineinfile:
dest: /etc/sysctl.conf
regexp: "{{ item.regexp }}"
line: "{{ item.line }}"
with_items:
- { regex...
PHP + MySQL transactions examples
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The idea I generally use when working with transactions looks like this (semi-pseudo-code):
try {
// First of all, let's begin a transaction
$db->beginTransaction();
// A set of queries; if one fails, an exception should be thrown
$db->q...
How can I make the Android emulator show the soft keyboard?
I'm debugging an issue with the soft keyboard display not displaying when it should. However, I don't have a device handy for testing. The problem is that the emulator never shows the soft keyboard .
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How to scale threads according to CPU cores?
I want to solve a mathematical problem with multiple threads in Java. my math problem can be separated into work units, that I want to have solved in several threads.
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Best way to detect that HTML5 is not supported
The standard way to deal with situations where the browser does not support the HTML5 <canvas> tag is to embed some fallback content like:
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-didSelectRowAtIndexPath: not being called
I'm writing an iOS app with a table view inside a tab view. In my UITableViewController , I implemented -tableView:didSelectRowAtIndexPath: , but when I select a row at runtime, the method isn't being called. The table view is being populated though, so I know that other tableView methods in my c...