Create a list to be inserted into a second level list of the mapping parameter

Helper function to support configuration of a Clinical Timelines module.

Usage

set_event(
  start_dt_var,
  end_dt_var = NULL,
  start_dy_var = NULL,
  end_dy_var = NULL,
  detail_var = NULL
)

start_dt_var: Character name of the variable that contains either the event start dates (for interval events) or merely timepoints (e.g. milestones). The variable name must be present in the data frame under which the event is listed.
end_dt_var: Character name of the variable that contains the event end dates. Needs to be provided for interval events, but set to NULL for timepoints. The variable name must be present in the data frame under which the event is listed.
start_dy_var: Similar to start_dt_var, but refers to the study relative days (instead of dates). The variable name must be present in the dataset under which the event is listed. Can be set to NULL to let the module calculate the study days according to SDTM standard rules.
end_dy_var: Similar to end_dt_var, but refers to the study relative days (instead of dates). The variable name must be present in the dataset under which the event is listed. Can be set to NULL to let the module calculate the study days according to SDTM standard rules.
detail_var: Character name of the variable that contains further descriptive information that shall be displayed for the event. Can be set to NULL for no further information.

A list that could directly be used as third level list for the mapping