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What is the EAFP principle in Python?
...e assumes the existence of valid keys or attributes and catches exceptions if the assumption proves false. This clean and fast style is characterized by the presence of many try and except statements. The technique contrasts with the LBYL style common to many other languages such as C.
An example ...
How do I execute a command and get the output of the command within C++ using POSIX?
..._ptr<FILE, decltype(&pclose)> pipe(popen(cmd, "r"), pclose);
if (!pipe) {
throw std::runtime_error("popen() failed!");
}
while (fgets(buffer.data(), buffer.size(), pipe.get()) != nullptr) {
result += buffer.data();
}
return result;
}
Pre-C++11 version:...
Laravel redirect back to original destination after login
...irect the user to "/login"
// and stores the url being accessed on session
if (Auth::guest()) {
return redirect()->guest('login');
}
return $next($request);
On login action:
// redirect the user back to the intended page
// or defaultpage if there isn't one
if (Auth::attempt(['email' =>...
Angularjs Template Default Value if Binding Null / Undefined (With Filter)
...
This doesn't work if you need to display a '0' value in column
– neel shah
Jun 23 '14 at 11:30
6
...
MySQL: Insert record if not exists in table
...Rupert | Somewhere | 022 |
+----+--------+-----------+------+
Insert a different record:
INSERT INTO table_listnames (name, address, tele)
SELECT * FROM (SELECT 'John', 'Doe', '022') AS tmp
WHERE NOT EXISTS (
SELECT name FROM table_listnames WHERE name = 'John'
) LIMIT 1;
Query OK, 1 row af...
How to determine if one array contains all elements of another array
...
If using the OP's definition of a1 and a2, and a1 "containing all elements of" a2, I think this should be _ (a1 & a2).size == a2.size _ since a2 is the smaller array, which should have all elements included in the larger ...
What happens to a declared, uninitialized variable in C? Does it have a value?
If in C I write:
10 Answers
10
...
How do I check if a property exists on a dynamic anonymous type in c#?
... public static bool IsPropertyExist(dynamic settings, string name)
{
if (settings is ExpandoObject)
return ((IDictionary<string, object>)settings).ContainsKey(name);
return settings.GetType().GetProperty(name) != null;
}
var settings = new {Filename = @"c:\temp\q.txt"};
...
How can you determine a point is between two other points on a line segment?
...
Check if the cross product of (b-a) and (c-a) is 0, as tells Darius Bacon, tells you if the points a, b and c are aligned.
But, as you want to know if c is between a and b, you also have to check that the dot product of (b-a) and ...
Modelling an elevator using Object-Oriented Analysis and Design [closed]
...all active elevators (not in maintenance).
The scheduling will be like:
if available pick a standing elevator for this floor.
else pick an elevator moving to this floor.
else pick a standing elevator on an other floor.
else pick the elevator with the lowest load.
Each elevator has a set of stat...