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value::to_number (1 of 3 overloads)
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Return the stored number cast to an arithmetic type.

Synopsis
template<
    class T>
T
to_number(
    boost::system::error_code& ec) const noexcept;
Description

This function attempts to return the stored value converted to the arithmetic type T which may not be bool:

  • If T is an integral type and the stored value is a number which can be losslessly converted, the conversion is performed without error and the converted number is returned.
  • If T is an integral type and the stored value is a number which cannot be losslessly converted, then the operation fails with an error.
  • If T is a floating point type and the stored value is a number, the conversion is performed without error. The converted number is returned, with a possible loss of precision.
  • Otherwise, if the stored value is not a number; that is, if this->is_number() returns false, then the operation fails with an error.
Constraints
std::is_arithmetic< T >::value && ! std::is_same< T, bool >::value
Complexity

Constant.

Exception Safety

No-throw guarantee.

Return Value

The converted number.

Parameters

Name

Description

ec

Set to the error, if any occurred.


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