#include <bdlb_nullableallocatedvalue.h>
List of all members.
Detailed Description
template<class TYPE>
class bdlb::NullableAllocatedValue< TYPE >
This template class extends the set of values of its value-semantic TYPE parameter to include the notion of a "null" value. If TYPE is fully value-semantic, then the augmented type NullableAllocatedValue<TYPE> will be as well. In addition to supporting all homogeneous value-semantic operations, conversions between comparable underlying value types is also supported. Two nullable objects with different underlying types compare equal if their underlying types are comparable and either (1) both objects are null or (2) the non-null values compare equal. Attempts to copy construct, copy assign, or compare incompatible values types will fail to compile. The NullableAllocatedValue template can be instantiated on an incomplete type, but it cannot be instantiated on a type that overloads operator&.
See Component bdlb_nullableallocatedvalue
Member Typedef Documentation
Constructor & Destructor Documentation
Create a nullable object having the null value. Optionally specify a basicAllocator used to supply memory. If basicAllocator is 0, the currently installed default allocator is used.
Create a nullable object having the value of the specified original object. Optionally specify a basicAllocator used to supply memory. If basicAllocator is 0, the currently installed default allocator is used.
Create a nullable object having the specified value. Optionally specify a basicAllocator used to supply memory. If basicAllocator is 0, the currently installed default allocator is used.
Member Function Documentation
Assign to this object the value of the specified rhs, and return a reference providing modifiable access to this object.
Assign to this object the value of the specified rhs, and return a reference providing modifiable access to the underlying TYPE object.
Efficiently exchange the value of this object with the value of the specified other object. This method provides the no-throw exception-safety guarantee. The behavior is undefined unless this object was created with the same allocator as other.
Assign to this object the specified value, and return a reference providing modifiable access to the underlying TYPE object.
Assign to this object the default value for TYPE, and return a reference providing modifiable access to the underlying TYPE object.
template<class TYPE>
template<class STREAM >
Assign to this object the value read from the specified input stream using the specified version format, and return a reference to stream. If stream is initially invalid, this operation has no effect. If version is not supported, this object is unaltered and stream is invalidated, but otherwise unmodified. If version is supported but stream becomes invalid during this operation, this object has an undefined, but valid, state. Note that no version is read from stream. See the bslx package-level documentation for more information on BDEX streaming of value-semantic types and containers.
Reset this object to the default constructed state (i.e., to have the null value).
Return a reference providing modifiable access to the underlying TYPE object. The behavior is undefined unless this object is non-null.
template<class TYPE>
template<class STREAM >
Write the value of this object, using the specified version format, to the specified output stream, and return a reference to stream. If stream is initially invalid, this operation has no effect. If version is not supported, stream is invalidated, but otherwise unmodified. Note that version is not written to stream. See the bslx package-level documentation for more information on BDEX streaming of value-semantic types and containers.
Return true if this object is null, and false otherwise.
Return the maximum valid BDEX format version, as indicated by the specified versionSelector, to be passed to the bdexStreamOut method. Note that it is highly recommended that versionSelector be formatted as "YYYYMMDD", a date representation. Also note that versionSelector should be a compile-time-chosen value that selects a format version supported by both externalizer and unexternalizer. See the bslx package-level documentation for more information on BDEX streaming of value-semantic types and containers.
Return the most current BDEX streaming version number supported by this class. (See the package-group-level documentation for more information on BDEX streaming of container types.)
Return the allocator used by this object to supply memory.
Format this object to the specified output stream at the (absolute value of) the optionally specified indentation level and return a reference to stream. If level is specified, optionally specify spacesPerLevel, the number of spaces per indentation level for this and all of its nested objects. If level is negative, suppress indentation of the first line. If spacesPerLevel is negative, format the entire output on one line, suppressing all but the initial indentation (as governed by level). If stream is not valid on entry, this operation has no effect.
Return a reference providing non-modifiable access to the underlying TYPE object. The behavior is undefined unless this object is non-null.
The documentation for this class was generated from the following file:
