Optional Readonlybuiltconsulted when there is no environment at hand
Optional Readonlyenvironmentresolve the name here first, so a definition in the analyzed code shadows the built-in as it does in R
Optional Readonlysignaturesfills in what the built-in definitions do not state, for namespaced names
Optional Readonlyversionthe package version to ask the signature database for (its latest by default)
Where to look up what flowR knows about a function, in that order: the name as it resolves here, the built-in definitions, and the signature database for the rest.