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Conveniently Declaring Compile-Time Strings in C++
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I haven't seen anything to match the elegance of Scott Schurr's str_const presented at C++ Now 2012. It does require constexpr though.
Here's how you can use it, and what it can do:
int
main()
{
constexpr str_const my_string = "Hello, world!";
static_assert(my_string.size() == 13,...
Weird PHP error: 'Can't use function return value in write context'
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You mean
if (isset($_POST['sms_code']) == TRUE ) {
though incidentally you really mean
if (isset($_POST['sms_code'])) {
share
|
improve thi...
Installing Python packages from local file system folder to virtualenv with pip
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The equivalent easy_install command is easy_install --allow-hosts=None --find-links file:///srv/pkg/mypackage mypackage
– Wilfred Hughes
Dec 13 '17 at 16:23
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Types in MySQL: BigInt(20) vs Int(20)
...264 (22003): Out of range value for column 'id' at row 1
mysql> SET sql_mode = '';
Query OK, 0 rows affected, 1 warning (0,00 sec)
mysql> INSERT INTO `test` (`id`) VALUES (401421228216);
Query OK, 1 row affected, 1 warning (0,06 sec)
mysql> SELECT * FROM `test`;
+------------+
| id ...
No generic implementation of OrderedDictionary?
... private KeyedCollection2<TKey, KeyValuePair<TKey, TValue>> _keyedCollection;
/// <summary>
/// Gets or sets the value associated with the specified key.
/// </summary>
/// <param name="key">The key associated with the value to get or...
How to create a video from images with FFmpeg?
...utput framerate
ffmpeg -r 1/5 -i img%03d.png -c:v libx264 -vf fps=25 -pix_fmt yuv420p out.mp4
Alternatively the format video filter can be added to the filter chain to replace -pix_fmt yuv420p like "fps=25,format=yuv420p". The advantage of this method is that you can control which filter goes...
Getting key with maximum value in dictionary?
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@oba2311 max_value = max(stats.values()); {key for key, value in stats.items() if value == max_value}
– A. Coady
Apr 4 '17 at 0:37
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Is there a way to instantiate objects from a string holding their class name?
...ce() { return new T; }
typedef std::map<std::string, Base*(*)()> map_type;
map_type map;
map["DerivedA"] = &createInstance<DerivedA>;
map["DerivedB"] = &createInstance<DerivedB>;
And then you can do
return map[some_string]();
Getting a new instance. Another idea is ...
How do I get the result of a command in a variable in windows?
... be passed argument with %, for example: for /f "delims=" %%i in ('date +%F_%H-%M-%S') do set now=%%i
– dma_k
May 4 '16 at 9:17
1
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When to use in vs ref vs out
...f myfuncOut and myfuncRef are identical as expected.
outRefTest.myfunc:
IL_0000: nop
IL_0001: ldc.i4.0
IL_0002: starg.s 00
IL_0004: ldarg.0
IL_0005: stloc.0
IL_0006: br.s IL_0008
IL_0008: ldloc.0
IL_0009: ret
outRefTest.myfuncOut:
IL_0000: ...