Error Codes

The input deck and maths parser in EPOCH use various named error codes to report on errors which occur during the evaluation of the input deck. These codes are

• c_err_none - No error. Set an error code to c_err_none to state that no error has occurred.
• c_err_unknown_block - In the input deck a block has been found which is not known. This should be returned in custom_blocks_handle_element if it is passed any block that it has not been written to handle.
• c_err_unknown_element - In the input deck an element of a valid block has been found which is not known. This should be returned in custom_blocks_handle_element if an element is requested which is unknown.
• c_err_preset_element - An element of the input deck has already been set and is being set again. Usually this is an indication of a malformed input deck file, so custom_blocks_handle_element should try to identify such situations and return this error message if subsequent attempts to set the variable are being ignored.
• c_err_preset_element_use_later - An element of the input deck has already been set and is being set again. Usually this is an indication of a malformed input deck file, so custom_blocks_handle_element should try to identify such situations and return this error message if the subsequent attempts to set the variable override previous ones.
• c_err_bad_value - A value which is being evaluated for the right hand side of an element assignment is in some way invalid. Internally to the code this usually means that a string which must be interpreted as a maths expression or numerical constant is in some way malformed. It is also acceptable to return this error code when a value has been passed which is invalid for some other reason (the value is outside an acceptable range, etc.)
• c_err_missing_elements - This is an error code returned when the code is testing to make sure that all necessary elements of an input deck file have been specified. It should be returned when some required parameter is missing in the subroutine custom_blocks_check.
• c_err_terminate - This error code means that the code is in a state where execution is impossible and the code must terminate once the input deck has been read. Some other error codes automatically set c_err_terminate, but it can always be IOR’ed with any error code to force the code to exit. Note that just returning c_err_terminate will cause the code to silently quit.
• c_err_required_element_not_set - This means that the code cannot parse an input deck element since another element which must be known beforehand has not been set. This is intended for things like setting the species information where the number of species must be known in advance. This error code uses the extended error string to give user friendly feedback. If you return this error code then you should set extended_error_string to be equal to the name of the required element which has not been set. If multiple previous elements are required then the code should be set up so that it checks for the presence of the required elements in order and reports on missing elements so that the end user can fix them one by one.
• c_err_pp_options_wrong - If you’ve written a section of the code that is controlled by preprocessor options then you should return this error message if someone attempts to set input deck elements which refer to that part when the correct preprocessor options are not used. This means that the user is aware of the fact that the requested feature will not be active. This error code also uses the extended error string to give user friendly feedback. If you return this error code, you should set the string extended_error_string to the define command that would turn on the requested feature of the code ("-DPER_PARTICLE_WEIGHT", for example).
• c_err_other - This error code is a catch all error which causes the code to quit with a sarcastic error message. It’s mainly intended for debugging and is used before the final error code is implemented.