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#ifdef vs #if - which is better/safer as a method for enabling/disabling compilation of particular s
...rather than 0/1 in your #define, and because the value is a single lexical token, it's the one time you don't need parentheses around it.
#define DEBUG_ENABLED true
instead of
#define DEBUG_ENABLED (1)
share
...
What is the difference between ${var}, “$var”, and “${var}” in the Bash shell?
...happen in a particular order, and some have specific use cases.
Braces as Token Delimiters
The ${var} syntax is primarily used for delimiting ambiguous tokens. For example, consider the following:
$ var1=foo; var2=bar; var12=12
$ echo $var12
12
$ echo ${var1}2
foo2
Braces in Array Expansions
T...
How to make sure that string is valid JSON using JSON.NET
...method).
(Using JSON.Net)
Simplest way would be to Parse the string using JToken.Parse, and also to check if the string starts with { or [ and ends with } or ] respectively (added from this answer):
private static bool IsValidJson(string strInput)
{
if (string.IsNullOrWhiteSpace(strInput)) { ret...
Make Https call using HttpClient
....github.com");
client.DefaultRequestHeaders.Add(
"Authorization",
"token 123456789307d8c1d138ddb0848ede028ed30567");
client.DefaultRequestHeaders.Accept.Add(
new MediaTypeWithQualityHeaderValue("application/json"));
client.DefaultRequestHeaders.Add(
"User-Agent",
"Mozilla/5.0 (Wi...
Adding a simple UIAlertView
...u want the alert to show, do this:
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"ROFL"
message:@"Dee dee doo doo."
delegate:self
...
Python List vs. Array - when to use?
...discontiguous and sparse arrays, and I think some pluggable strategies for allocating memory for large arrays... some of these advanced features will make it user less memory, while others will improve performance by using more memory.
– Dan Lenski
Oct 29 '14 a...
How can a web application send push notifications to iOS devices? [closed]
...ive app is registered for push notification, it can send the authorization token to the server, which can be used in conjunction with the certificate used to provision the native client, to send the push notifications to the mobile device.
As specified in another answer, one option is to 'wrap' yo...
How far can memory leaks go?
I've run into memory leaks many times. Usually when I'm malloc -ing like there's no tomorrow, or dangling FILE * s like dirty laundry. I generally assume (read: hope desperately) that all memory is cleaned up at least when the program terminates. Are there any situations where leaked memory won't ...
Java heap terminology: young, old and permanent generations?
...lowing.
Eden Space (heap): The pool from which memory is initially allocated
for most objects.
Survivor Space (heap): The pool containing objects that have survived
the garbage collection of the Eden
space.
Tenured Generation (heap): The pool containing objects that have existed
...
How to print a string in fixed width?
...
the % character informs python it will have to substitute something to a token
the s character informs python the token will be a string
the 5 (or whatever number you wish) informs python to pad the string with spaces up to 5 characters.
In your specific case a possible implementation could look...