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Function any_cast

boost::any_cast —

Custom keyword cast for extracting a value of a given type from an any.


template<typename ValueType> ValueType any_cast(const any & operand);
template<typename ValueType> const ValueType * any_cast(const any * operand);
template<typename ValueType> ValueType * any_cast(any * operand);


Returns: If passed a pointer, it returns a similarly qualified pointer to the value content if successful, otherwise null is returned. If passed a value or reference, it returns a copy of the value content if successful.
Throws: Overloads taking an any pointer do not throw; the overload taking an any value or reference throws bad_any_cast if unsuccessful.
Rationale: The value/reference version returns a copy because the C++ keyword casts return copies.

Copyright 2001 Kevlin Henney