unsafe fn env_binding(env: SEXP, name: &CStr) -> Option<SEXP>Expand description
Look up a variable bound directly in a single environment frame (no search
of enclosing frames — this is Rf_findVarInFrame, not Rf_findVar).
Returns None if env is not itself an environment, or if name has no
binding in it. Active bindings are forced transparently by R, same as any
other variable read.
§Safety
Must be called from R’s main thread.