In C++ specifies constructors and conversion operators that don't allow implicit conversions or copy-initialization. In C# declares a user-defined type conversion operator that must be invoked with a cast. For MS SQL Server for-xml-EXPLICIT mode use the [for-xml-explicit] tag
Questions tagged [explicit]
405 questions
11
votes
2 answers
Implicit conversion to explicit bool-types for sorting containers?
I am playing around with the new explicit for cast-operators. If you write something like
struct Data {
explicit operator string();
};
It is not possible to accidentally convert Data to string. The darget data type bool is an exception: In…
towi
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11
votes
3 answers
Compiler replaces explicit cast to my own type with explicit cast to .NET type?
I have the following code:
public struct Num
{
private readonly T _Value;
public Num(T value)
{
_Value = value;
}
static public explicit operator Num(T value)
{
return new Num(value);
…
Martin Mulder
- 12,642
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11
votes
2 answers
explicit operator bool error
I get the Compiler Error C2071 when I try to implement the explicit operator bool:
class C
{
public:
explicit operator bool() const
{
return !!*this;
}
};
Why? How can I solve this problem?
I'm using Visual Studio 2012 RC.
Nick
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10
votes
1 answer
How to check if type is explicitly/implicitly constructible?
How can it be checked that some type is explicitly (or vice versa implicitly) constructible from other type? Is it any SFINAE trick in this situation?
I can write is_explicitly_constructible as a combination of std::is_constructible and…
Constructor
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10
votes
1 answer
Why is this operator= call ambiguous?
I was making a thin derived class with a forwarding constructor. (Bear with me, I must use GCC 4.7.2, which lacks inherited constructors).
On the first try, I forgot to add the explicit keyword and got an error. Could someone explain exactly why…
AndyJost
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10
votes
2 answers
starting android service using explicit vs implicit intent
According to the standard Android documentation, the prefered way to start a service (started service that is) is to use an explicit intent like this:
// Using explicit intent:
Intent serviceIntent = new Intent(getApplicationContext(),…
user504342
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10
votes
3 answers
Why are vector's multi-argument constructors taking construction parameters not marked "explicit"?
I observed the following vector constructors in the Standard C++ library
explicit vector(size_type n);
vector(size_type n, const T& value, const Allocator& = Allocator());
Is there a reason why the second constructor is not marked explicit? This…
Johannes Schaub - litb
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9
votes
5 answers
Strings and ints, implicit and explicit
Had a coworker ask me this, and in my brain befuddled state I didn't have an answer:
Why is it that you can do:
string ham = "ham " + 4;
But not:
string ham = 4;
If there's an implicit cast/operation for string conversion when you are…
Rostov
- 2,516
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9
votes
1 answer
Prevent implicit conversion but allow list initialisation?
Let's say I have a class FunctionWrapper defined like this:
struct FunctionWrapper
{
FunctionWrapper(std::function f);
// ... plus other members irrelevant to the question
};
I'd like to prevent implicit conversions from…
Angew is no longer proud of SO
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9
votes
1 answer
Should I really massively introduce the explicit keyword?
When I used the (recently released) Cppcheck 1.69 on my code1, it showed a whole lot of messages where I expected none. Disabling noExplicitConstructor proved that all of them were of exactly this kind.
But I found that I'm not the only one with a…
Wolf
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9
votes
1 answer
Why doesn't Option Explicit catch ReDim ?
Does anyone know why this doesn't throw a Variable not defined error when I compile it?
'Class1.cls'
Option Explicit
Public Sub foo()
ReDim fubar(1 To 2, 1 To 1)
End Sub
Am I misunderstanding how Option Explicit is supposed to work? Or is…
RBarryYoung
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9
votes
0 answers
removing an explicit mandatory label using icacls
I was doing some experimentation with integrity levels and icacls on Windows 7. I set mandatory integrity levels, so that I get something that looks like this:
C:\Debug>icacls test.exe
test.exe Everyone:(I)(RX)
…
chut7
- 103
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8
votes
2 answers
.NET - How is explicit cast with "as" different (internally) from (someType)someobject, and why?
I understand that when you use an explicit cast like this:
(someType)someobject
you can get an invalid cast exception if someobject is not really someType.
As well I understand that when you cast with as like this:
myObject = someObject as…
richard
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8
votes
1 answer
8
votes
2 answers
explicit non-single parameter constructor
Can anyone explain why does non-single parameter constructor marked as explicit compile?
As far as I understand this is absolutely useless keyword here, so why does this compile without error?
class X
{
public:
explicit X(int a, int b) { /* ...…
axe
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