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Understanding the meaning of the term and the concept - RAII (Resource Acquisition is Initialization
...rce, one constructor. UTSTTC is just one application of that, RAII is much more.
Resource Management sucks. Here, resource is anything that needs cleanup after use. Studies of projects across many platforms show the majority of bugs are related to resource management - and it's particularly bad on ...
What is the purpose of class methods?
...me time? Which way of calling class methods of an object is "better", or "more idiomatic": obj.cls_mthd(...) or type(obj).cls_mthd(...)?
– Alexey
Feb 27 '18 at 12:43
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What exactly is a C pointer if not a memory address?
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What is the most efficient/elegant way to parse a flat table into a tree?
.... Read "Trees and Hierarchies in SQL for Smarties" by Joe Celko for a lot more information on these designs.
I usually prefer a design called Closure Table (aka "Adjacency Relation") for storing tree-structured data. It requires another table, but then querying trees is pretty easy.
I cover Clos...
Best way to combine two or more byte arrays in C#
...;> method. It's only slightly slower than the C# yield operator, but is more concise and more elegant.
IEnumerable<byte> rv = a1.Concat(a2).Concat(a3);
If you have an arbitrary number of arrays and are using .NET 3.5, you can make the System.Buffer.BlockCopy solution more generic like th...
Sorting HashMap by values [duplicate]
... }
}
return sortedMap;
}
Just a kick-off example. This way is more useful as it sorts the HashMap and keeps the duplicate values as well.
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LISTAGG in Oracle to return distinct values
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from (
select distinct the_column
from the_table
) t
If you need more columns, something like this might be what you are looking for:
select col1, listagg(col2, ',') within group (order by col2)
from (
select col1,
col2,
row_number() over (partition by col1, col2 orde...
What blocks Ruby, Python to get Javascript V8 speed? [closed]
...ave decades of experience (I'm talking individually – collectively it's more like centuries) in creating high-performance execution engines for dynamic OO languages. They are basically the same people who also created the Sun HotSpot JVM (among many others).
Lars Bak, the lead developer, has bee...
throwing an exception in objective-c/cocoa
...ay as apposed to the @throw([NSException exceptionWith…]) approach as it more concise.
– Sam Soffes
Jun 18 '10 at 19:56
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Task vs Thread differences [duplicate]
... a separate thread, rather than executing on the thread pool etc.
Task is more than just an abstraction of "where to run some code" though - it's really just "the promise of a result in the future". So as some different examples:
Task.Delay doesn't need any actual CPU time; it's just like setting...