Exception

• An exception signifies the presence of an abnormal condition which requires special operable techniques
• Error Types
  • Syntax Error
    • Mistake in the pre-defined syntax
  • Runtime Error
    • Runtime errors are known as Exceptions.
  • Logical Error
    • Logical mistake in the program, abnormal output

Exception Handling

• try
  • The code in try {…} is executed.
• catch
  • This Statement is executed if an exception is thrown in the try-block.
• exception_var
  • An optional identifier to hold an exception object for the associated catch-block.
• finally
  • Statements that are executed after the try statement completes.
  • These statements execute regardless exception was thrown or caught
• throw
  • The throw statement defines a custom error

try {
  try_statements
}
catch (exception_var) {
  catch_statements
}
finally {
  finally_statements
}

try {
  // generates an exception
  throw 'myException'; 
} catch (e) {
  // statements to handle any exceptions
  console.log(e);
} finally {
    console.log('finally');
}
// myException
// finally