11. Errors and Error Handling

11 Errors and Error Handling

11.1 Terminology

Errors can roughly be divided into four different types:

• Compile-time errors
• Logical errors
• Run-time errors
• Generated errors

A compile-time error, for example a syntax error, does not cause much trouble as it is caught by the compiler.

A logical error is when a program does not behave as intended, but does not crash. An example is that nothing happens when a button in a graphical user interface is clicked.

A run-time error is when a crash occurs. An example is when an operator is applied to arguments of the wrong type. The Erlang programming language has built-in features for handling of run-time errors.

A run-time error can also be emulated by calling erlang:error(Reason) or erlang:error(Reason, Args) (those appeared in Erlang 5.4/OTP-R10).

A run-time error is