could be empty

ValentinKaisermayer · ValentinKaisermayer · commit 2718c4e723c8 · 2022-03-22T16:26:07.000+01:00
diff --git a/src/utils.jl b/src/utils.jl
@@ -473,6 +473,7 @@ function mergedefaults(defaults, varmap, vars)
 end
 
 function promote_to_concrete(vs)
+    isemtpy(vs) && return vs
     T = eltype(vs)
     if Base.isconcretetype(T) # nothing to do
         vs
