Parse within varying arguments
parse_varyarguments_w(sim_args, name)
A named list with special model formula syntax. See details and examples for more information. The named list may contain the following:
fixed: This is the fixed portion of the model (i.e. covariates)
random: This is the random portion of the model (i.e. random effects)
error: This is the error (i.e. residual term).
The name of the within simulation condition. This is primarily an internal function.