Boost.Any is a C++ library that offers a safe, generic container for single values of different value types.
Boost.Any is a C++ library that offers a safe, generic container for single values of different value types.
Questions tagged [boost-any]
118 questions
2
votes
1 answer
C++ Switch on Data Type
I have an Attribute class that has an Enum specifying the type of the attribute (INT_64, UINT 64, INT_32, STRING, DOUBLE, etc.). This Attribute class uses boost::any to hold a vector of the types specified by the enum.
At the moment in order to work…
Samuel O'Malley
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2
votes
1 answer
boost::spirit::hold_any memory corruption
I have a large code base that can use boost::any or boost::spirit::hold_any (depending on a macro definition).
hold_any seems to be compatible with boost::any (e.g. How to print boost::any to a stream? or Type erasure - Part IV) and faster (Why you…
manlio
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2
votes
2 answers
Boost::any reference to stored value not compiling
I'm trying to write a generic configuration class that holds parameters like this (simplified greatly):
class Parameter
{
public:
Parameter(boost::any value, bool isRequired)
: value(value), isRequired(isRequired) {}
bool isSet;
bool…
Fadecomic
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2
votes
1 answer
nullptr as flag value for boost::any map
If I set up a generic container map using boost::any, and use the new nullptr from C++11 as an initialization value akin to an isset() type operation, are there any potential pitfalls?
For example:
std::map map;
map["A"] =…
Fadecomic
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2
votes
1 answer
Boost MSM, transition won't happen despite boost::any being used as an event
I'm developing a state machine using boost MSM framework. Their tutorial states that boost::any can be used as a "Kleene event", allowing transition on any event being fired, if the current state is the source state. This doesn't work for me,…
Kikosha
- 343
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2
votes
1 answer
Is it possible to avoid overhead while using boost_any?
I'd like to use boost::any as a universal type to store in a container and to pass to different functions. But inside these functions I always know the real type, so in runtime I don't need any type safety checks and the imposed overhead,…
lizarisk
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2
votes
1 answer
Is Adding boost::any in a boost::property_tree Possible?
I am trying to store a boost::any type to a boost property tree. Here is some runnable example:
#include
#include
#include
#include
#include
#include
#include…
Subhamoy S.
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2
votes
1 answer
use `(boost::any a)` instead of `(const boost::any& a)` to prevent reference-to-reference
First comes the definition of our new function object, contains_t. It
could have inherited from the helper class std::unary_function (part
of the C++ Standard Library, intended to facilitate the creation of
the correct typedefs) and have the…
q0987
- 34,938
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2
votes
1 answer
Can boost::any_cast(any&) be sped up?
It looks like calls to boost::any_cast(any&) call some expensive typechecking to make sure that the cast is valid. Specifically, it calls performs the following test to make sure the cast is legal:
std::strcmp(operand->type().name(),…
BenRI
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1
vote
1 answer
C++ container of any/variant each element having unchanging type
I am using std::map to store my library's settings. Each setting only uses a single underlying value type and I want to enforce this during configuration calls to set() or similar. Settings are initialized with default…
paperjam
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1
vote
1 answer
Recovering a function pointer from a boost::any
I want to use boost::any to store heterogeneous function pointers. I get an exception when I try to use boost::any_cast to recast to the function pointer.
Is what I want to do even allowed?
.h:
typedef void(*voidFunction)(void);
struct…
Smash
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1
vote
0 answers
Understanding Boost::any with function parameters, pointers, and proper casting
I have a fundamental understanding of using boost::any, but I've inherited some code that perplexes me. I am trying to understand the implementation and whether there is a better/correct way to implement.
Basically, I have a series of functions…
striker
- 11
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1
vote
1 answer
Implementing boost any like class
I am trying to emulate boost::any for a toy language of mine, following the accepted answer from the following question,
Accessing Values in a Class Similar to boost::any
I can have,
Element e1 = 11;
Element e2 = 12.1;
now I would like to overload…
Hamza Yerlikaya
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1
vote
1 answer
boost::any_cast to my custom class
I'm new to some boost feature and I'm facing some issues trying to cast a reference to boost::any to a reference to a custom class (for now it's empty, I'm still figuring out the content of the class).
Shortly, I have:
class MyClass
{
public:
…
XectX
- 36
- 4
1
vote
3 answers
boost::any compare value?
I have a vector of boost::any and would like to find the index of a 'any' in this vector.
Something like this :
vector values;
any valueISearch = ...;
find(valueISearch);
For this I try to compare 2 any values with the following method :
…
Spectral
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