reformulas (random effects formulas) is a utility package for processing "lme4-style" random effects formulas in R (i.e., formulas where the random effects are included in the form (f|g) as components of an overall model formula, where f represents a sub-formula for the varying effects and g represents a sub-formula for the grouping variable(s). WWW: https://cran.r-project.org/web/packages/reformulas/