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How to print an exception in Python?
...rint the exception, it is better to use print(repr(e)); the base Exception.__str__ implementation only returns the exception message, not the type. Or, use the traceback module, which has methods for printing the current exception, formatted, or the full traceback.
– Martijn Pi...
What are five things you hate about your favorite language? [closed]
...ld be matched to another NULL value. If you understand this (what also is called ternary logic) than you might understand the reason for introducing the "IS" operator for testing against NULL.
– Alex
Aug 26 '10 at 16:58
...
What does send() do in Ruby?
... some method reacts (because its name matches the first argument).
Practically speaking, those lines are equivalent:
1.send '+', 2
1.+(2)
1 + 2
Note that send bypasses visibility checks, so that you can call private methods, too (useful for unit testing).
If there is really no variable before...
Match multiple cases classes in scala
... matcher(l: Foo): String = {
l match {
case A() => "A"
case B(_) | C(_) => "B"
case _ => "default"
}
}
If you must, must, must extract the parameter and treat them in the same code block, you could:
def matcher(l: Foo): String = {
l match {
case A() => "A"
ca...
How to remove convexity defects in a Sudoku square?
...surements[
ColorNegate@Binarize[srcAdjusted], {"ConvexArea", "Mask"}][[All,
2]];
largestComponent = Image[SortBy[components, First][[-1, 2]]]
By filling this image, I get a mask for the sudoku grid:
mask = FillingTransform[largestComponent]
Now, I can use a 2nd order derivative fil...
How to export/import PuTTy sessions list?
...utty-sessions.reg" HKEY_CURRENT_USER\Software\SimonTatham\PuTTY\Sessions
All settings:
regedit /e "%USERPROFILE%\Desktop\putty.reg" HKEY_CURRENT_USER\Software\SimonTatham
Powershell:
Only sessions:
reg export HKCU\Software\SimonTatham\PuTTY\Sessions ([Environment]::GetFolderPath("Desktop") ...
read complete file without using loop in java
...
If the file is small, you can read the whole data once:
File file = new File("a.txt");
FileInputStream fis = new FileInputStream(file);
byte[] data = new byte[(int) file.length()];
fis.read(data);
fis.close();
String str = new String(data, ...
What does -> mean in Python function definitions?
...
And the information is available as a .__annotations__ attribute.
– Martijn Pieters♦
Jan 17 '13 at 13:06
9
...
Assignment in an if statement
... = value as T;
if (t != null)
{
action(t);
}
}
Then call it with:
animal.AsIf<Dog>(dog => {
// Use dog in here
});
Alternatively, you could combine the two:
public static void AsIf<T>(this object value, Action<T> action) where T : class
{
// EVI...
How to increment a datetime by one day?
...
All of the current answers are wrong in some cases as they do not consider that timezones change their offset relative to UTC. So in some cases adding 24h is different from adding a calendar day.
Proposed solution
The follo...