Pointer Qualification Conversions, Casts, and Run-Time Type Identification

Cast Operators

This release of the C++ translator supports several new cast operators. These operators are defined in the ISO C++ draft as improved alternatives to the old cast operators, for example, (type)(expr) or type_name (expr) . For more information on these operators, see Stroustrup's Design and Evolution of C++.

The new cast operators are

static_cast< type > ( expr )

portable conversions that do not cast away constness

const_cast< type > ( expr )

pointer qualification conversions, including the unsafe conversions which cannot be performed implicitly

reinterpret_cast< type > ( expr )

nonportable conversions such as:

conversion from pointer to int and back
conversions between arbitrary pointers to objects
conversions between arbitrary pointers to functions

dynamic_cast< type > ( expr )

run-time type dependent pointer and reference conversions.

The new cast operators, except dynamic_cast , provide separate components of the functionality of the old casts that allow improved type checking. Any old-style cast can be expressed as a combination of the new casts. The new cast operators, other than const_cast , are not allowed to cast away constness on pointer, pointer to member, and reference conversions. See section 5.2.11 of the ISO draft for more information.

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