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How do I concatenate two strings in C?
...-terminator.
char* concat(const char *s1, const char *s2)
{
const size_t len1 = strlen(s1);
const size_t len2 = strlen(s2);
char *result = malloc(len1 + len2 + 1); // +1 for the null-terminator
// in real code you would check for errors in malloc here
memcpy(result, s1, len1);
...
How unique is UUID?
...om numbers. However, it seems to me that given enough time, it would eventually repeat it self, just by pure chance. Is there a better system or a pattern of some type to alleviate this issue?
...
Detect if an input has text in it using CSS — on a page I am visiting and do not control?
... script will work in Chrome, or Firefox with Greasemonkey or Scriptish installed, or in any browser that supports userscripts (i.e. most browsers, except IE).
See a demo of the limits of CSS plus the javascript solution at this jsBin page.
// ==UserScript==
// @name _Dynamically style inputs b...
How to define different dependencies for different product flavors
I am converting one of my apps to Gradle and would like to use the new build flavor features to have a paid and a free ad based flavor.
...
Django: Set foreign key using integer?
...
Yep:
employee = Employee(first_name="Name", last_name="Name")
employee.type_id = 4
employee.save()
ForeignKey fields store their value in an attribute with _id at the end, which you can access directly to avoid visiting the database.
The _id version of...
How to use a variable to specify column name in ggplot
...
"cumbersome"? Non-standard evaluation in R is ironically the most cumbersome "feature" I have ever encountered in a programming language. Truly maddening.
– jessexknight
Feb 4 at 18:10
...
Adding rounded corner and drop shadow to UICollectionViewCell
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Neither of these solutions worked for me. If you place all your subviews into the UICollectionViewCell content view, which you probably are, you can set the shadow on the cell's layer and the border on the contentView's layer to achieve both results.
cell.contentView.layer.corne...
Aliases in Windows command prompt
...ommand dropbox research points to the same directory as research.
As Rivenfall pointed out, it is a good idea to include a command that allows for convenient editing of the alias.cmd file. See alias above. If you are in a cmd session, enter cmd to restart cmd and reload the alias.cmd file.
When ...
Why use static_cast(x) instead of (int)x?
...e main reason is that classic C casts make no distinction between what we call static_cast<>(), reinterpret_cast<>(), const_cast<>(), and dynamic_cast<>(). These four things are completely different.
A static_cast<>() is usually safe. There is a valid conversion in the...
argparse module How to add option without any argument?
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As @Felix Kling suggested use action='store_true':
>>> from argparse import ArgumentParser
>>> p = ArgumentParser()
>>> _ = p.add_argument('-f', '--foo', action='store_true')
>>> args = p.parse_args()
>>> args.foo
False
&g...