std::length_error

Header: <stdexcept>

Defines a type of object to be thrown as exception. It reports errors that result from attempts to exceed implementation defined length limits for some object.

# Declarations

class length_error;

# Parameters

• what_arg: explanatory string
• other: another exception object to copy

# Return value

*this

# Notes

Because copying std::length_error is not permitted to throw exceptions, this message is typically stored internally as a separately-allocated reference-counted string. This is also why there is no constructor taking std::string&&: it would have to copy the content anyway.

Before the resolution of LWG issue 254, the non-copy constructor can only accept std::string. It makes dynamic allocation mandatory in order to construct a std::string object.

After the resolution of LWG issue 471, a derived standard exception class must have a publicly accessible copy constructor. It can be implicitly defined as long as the explanatory strings obtained by what() are the same for the original object and the copied object.

# Defect reports

# See also

• resize