fix literal value

src/utils.jl

@@ -9,6 +9,9 @@ but rather keep it as a numeric literal in the generated equations.
 struct LiteralParameter{P}
     p::P
 end
+# necessary for the macro
+_literalvalue(x) = x
+_literalvalue(p::LiteralParameter) = p.p
 
 """
     has_variable(eq, var)
@@ -63,7 +66,7 @@ If `value isa Num` return `value`.
 If `value isa `[`LiteralParameter`](@ref), replace it with its literal value.
 Otherwise, create a new MTK `@parameter`
 whose name is created from `variable` by adding the `extra` string.
-If `suffix = true` the extra is added at the end after a `_`. Otherwise
+If `suffix == true` the extra is added at the end after a `_`. Otherwise
 it is added at the start, then a `_` and then the variable name.
 
 For example,
@@ -133,7 +136,7 @@ macro convert_to_parameters(vars...)
         varname = QuoteNode(var)
         push!(expr.args,
             :($binding = ifelse(
-                $binding isa LiteralParameter, $(binding).p, ifelse(
+                $binding isa LiteralParameter, _literalvalue($(binding)), ifelse(
                 # don't do anyting if this is already a Num
                 $binding isa Num, $binding,
                 # Else, convert to modeling toolkit param.

test/runtests.jl

@@ -131,27 +131,38 @@ end
 end
 
 @testset "utility functions" begin
-    @variables x(t) = 0.5
-    p = new_derived_named_parameter(x, 0.2, "t")
-    @test ModelingToolkit.getname(p) == :x_t
-    @test default_value(p) == 0.2
-    p = new_derived_named_parameter(x, p, "lala")
-    @test ModelingToolkit.getname(p) == :x_t
-
-    A, B = 0.5, 0.5
-    C = first(@parameters X = 0.5)
-    @convert_to_parameters A B C
-    @test A isa Num
-    @test default_value(A) == 0.5
-    @test ModelingToolkit.getname(C) == :X
     # Test an untested clause:
     @test default_value(0.5) == 0.5
 
-    p = LiteralParameter(0.5)
-    p = new_derived_named_parameter(x, p, "t")
-    @test p == 0.5
+    @testset "derived" begin
+        @variables x(t) = 0.5
+        p = new_derived_named_parameter(x, 0.2, "t")
+        @test ModelingToolkit.getname(p) == :x_t
+        @test default_value(p) == 0.2
+        p = new_derived_named_parameter(x, p, "lala")
+        @test ModelingToolkit.getname(p) == :x_t
+    end
+
+    @testset "convert" begin
+        A, B = 0.5, 0.5
+        C = first(@parameters X = 0.5)
+        @convert_to_parameters A B C
+        @test A isa Num
+        @test default_value(A) == 0.5
+        @test ModelingToolkit.getname(C) == :X
+
+    end
+
+    @testset "literal in derived" begin
+        p = LiteralParameter(0.5)
+        p = new_derived_named_parameter(x, p, "t")
+        @test p == 0.5
+    end
+
+    @testset "literal in covert" begin
+        p = LiteralParameter(0.5)
+        @convert_to_parameters p
+        @test p == 0.5
+    end
 
-    p = LiteralParameter(0.5)
-    @convert_to_parameters p
-    @test p == 0.5
 end