support 0-arg functions

Author: shashi

src/RuntimeGeneratedFunctions.jl

@@ -46,7 +46,7 @@ struct RuntimeGeneratedFunction{argnames, cache_tag, context_tag, id} <: Functio
     body::Expr
     function RuntimeGeneratedFunction(cache_tag, context_tag, ex)
         def = splitdef(ex)
-        args, body = normalize_args(def[:args]), def[:body]
+        args, body = normalize_args(get(def, :args, [])), def[:body]
         id = expr_to_id(body)
         cached_body = _cache_body(cache_tag, id, body)
         new{Tuple(args), cache_tag, context_tag, id}(cached_body)

test/runtests.jl

@@ -27,10 +27,14 @@ ex3 = :(function (_du::T,_u::Vector{E},_p::P,_t::Any) where {T<:Vector,E,P}
     nothing
 end)
 
+
+f0 = @RuntimeGeneratedFunction(()->42)
 f1 = @RuntimeGeneratedFunction(ex1)
 f2 = @RuntimeGeneratedFunction(ex2)
 f3 = @RuntimeGeneratedFunction(ex3)
 
+@test f0() === 42
+
 @test f1 isa Function
 
 du = rand(2)