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Dictionary returning a default value if the key does not exist [duplicate]
...Value(key, out value);
and just ignore the return value. However, that really will just return default(TValue), not some custom default value (nor, more usefully, the result of executing a delegate). There's nothing more powerful built into the framework. I would suggest two extension methods:
pu...
Iterating each character in a string using Python
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If that seems like magic, well it kinda is, but the idea behind it is really simple.
There's a simple iterator protocol that can be applied to any kind of object to make the for loop work on it.
Simply implement an iterator that defines a next() method, and implement an __iter__ method on a c...
How to drop column with constraint?
...'alter table tbloffers drop constraint ['+dc.NAME+N']'
from sys.default_constraints dc
JOIN sys.columns c
ON c.default_object_id = dc.object_id
WHERE
dc.parent_object_id = OBJECT_ID('tbloffers')
AND c.name = N'checkin'
IF @@ROWCOUNT = 0 BREAK
EXEC (@sql)
END
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Is the practice of returning a C++ reference variable evil?
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In general, returning a reference is perfectly normal and happens all the time.
If you mean:
int& getInt() {
int i;
return i; // DON'T DO THIS.
}
That is all sorts of evil. The stack-allocated i will go away and you are referring to nothing. This is also evil:
int& get...
JavaScript curry: what are the practical applications?
...self—is useful in JavaScript; it is a technique for converting function calls with multiple arguments into chains of function calls with a single argument for each call, but JavaScript supports multiple arguments in a single function call.
In JavaScript—and I assume most other actual languages...
How to determine if binary tree is balanced?
... some fraction of the minimum path length, like a half or a quarter.
It really doesn't matter usually. The point of any tree-balancing algorithm is to ensure that you do not wind up in the situation where you have a million nodes on one side and three on the other. Donal's definition is fine in the...
PHP server on local machine?
...d I'm wanting to test my PHP files without uploading them to my host. Basically testing them on my own machine before I upload them. How do I do that?
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LINQ: Distinct values
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Oh so by "larger type" you may mean I still want all properties in the result even though I only want to compare a few properties to determine distinctness?
– The Red Pea
Sep 20 '16 at 14:31
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How to get year, month, day, hours, minutes, seconds and milliseconds of the current moment in Java?
...t an int to String, make use of String#valueOf().
If your intent is after all to arrange and display them in a human friendly string format, then better use either Java8's java.time.format.DateTimeFormatter (tutorial here),
LocalDateTime now = LocalDateTime.now();
String format1 = now.format(DateTi...
Unique Key constraints for multiple columns in Entity Framework
... third approach may not necessarily be the best. (I like the first one actually.) I personally prefer not having any EF artifacts carried over into my entity classes.
– Najeeb
Nov 11 '17 at 12:45
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