Exceptions

1
Exceptions
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• C Exceptions are used to propagate unexpected
  or severe errors.
• Section of code which may have error is put into
  try block.
• Any error which occurs in block is forwarded to
  exception handler designed by catch clause.
• Normal flow control is interrupted.

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• If current function does not catch function,
  exception propagation continues in the calling
  function.
• Destructors of local objects are executed as
  objects destroyed.
• Propagation continues until exception caught or
  main is exited.

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Catch clauses

• May have multiple catch clauses.
• Matching is done in order encountered.
• Derived classes will match specifications of base
  classes.
• May use () as catch clause, which matches any
  exception.

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Throw statement

• Exception started with throw statement.
• May throw an object of any type.
• Good design practice to derive exceptions from
  exception class.
• Message passed to constructor.
• provides what( ) function which returns message
  that is passed.

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Standard exceptions

• in ltstdexceptgt
• logic_error
• domain_error
• invalid_argument
• length_error
• out_of_range
• runtime_error
• range_error
• overflow_error
• underflow_error