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Double not (!!) operator in PHP
... you will get the boolean value FALSE.
It is functionally equivalent to a cast to boolean:
return (bool)$row;
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What are the advantages of using nullptr?
...s. Unlike C, C++ is a strongly typed language (C does not require explicit cast from void* to any type, while C++ mandates a explicit cast). This makes the definition of NULL specified by C standard useless in many C++ expressions. For example:
std::string * str = NULL; //Case 1
void (A::*p...
C# 'is' operator performance
...
Using is can hurt performance if, once you check the type, you cast to that type. is actually casts the object to the type you are checking so any subsequent casting is redundant.
If you are going to cast anyway, here is a better approach:
ISpecialType t = obj as ISpecialType;
if (t ...
How do you find the row count for all your tables in Postgres
...th their own tradeoffs.
If you want a true count, you have to execute the SELECT statement like the one you used against each table. This is because PostgreSQL keeps row visibility information in the row itself, not anywhere else, so any accurate count can only be relative to some transaction. Yo...
Android Studio - Ambiguous method call getClass()
....
Have a look at the Error report
The only workaround to this issue is to cast the instance you call getClass() on, to Object as follows:
((Object) this).getClass()
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Is there a way to suppress warnings in Xcode?
... Easy way to get the warning code: go to the Log Navigator (Command+7), select the topmost build, expand the log (the '=' button on the right), and scroll to the bottom.
– Neal Ehardt
Jan 25 '12 at 16:46
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Query an XDocument for elements by name at any depth
...n
TheDocument.Descendants( "{http://www.w3.org/2001/XMLSchema}Child" )
select
AnyElement;
ResultsTxt.AppendText( TheElements1.Count().ToString() );
//Example 2:
var TheElements2 =
from
AnyElement
in
TheDocument.Descendants( "{http://www.w3.org/2001/XMLSchema}Child" )
where
AnyE...
byte[] to hex string [duplicate]
...);
}
static string LinqConcat(byte[] data)
{
return string.Concat(data.Select(b => b.ToString("X2")).ToArray());
}
static string LinqJoin(byte[] data)
{
return string.Join("",
data.Select(
bin => bin.ToString("X2")
).ToArray());
}
static string LinqAgg(b...
Boolean vs boolean in Java
...e (bar)?1:0 illustrates that bar (boolean) cannot be implicitly converted (casted) into an int. I am bringing this up not to illustrate the details of implementation behind JVM, but to point out that in terms of low level considerations (as memory size) one does have to prefer values over type safet...
List of Delphi language features and version in which they were introduced/deprecated
...dynamic arrays to a pointer using the @ operator is only allowed when hard-casting the array.
More flexible namespace resolution of unit names
Delphi 10.1 Berlin
Native support for Utf8String and RawByteString type on all platforms
The [weak], [unsafe] and [volatile] attributes are support...