Utility function that checks if a specific user given parameter value an accepted time_step, in which case it returns TRUE An accepted time_step is considered to be: <<A character string, containing one of "day", "week", "month", "quarter" or "year". This can optionally be preceded by a (positive or negative) integer and a space, or followed by "s".>> (from https://www.rdocumentation.org/packages/base/versions/3.6.2/topics/seq.Date)

.is_value_valid_time_step(string_user_input, parameter_name)

Arguments

string_user_input

A string containing the value that the user passed for the tested string type parameter.

parameter_name

A string containing the name the tested parameter had in the initial function in which it was passed.

Value

TRUE if all tests were passed. Throws an error otherwise.