Cleanup some dead code (#243)

Author: sunxd3

Project.toml

@@ -1,6 +1,6 @@
 name = "JuliaBUGS"
 uuid = "ba9fb4c0-828e-4473-b6a1-cd2560fee5bf"
-version = "0.7.1"
+version = "0.7.2"
 
 [deps]
 AbstractMCMC = "80f14c24-f653-4e6a-9b94-39d6b0f70001"

src/model.jl

@@ -431,9 +431,8 @@ function check_var_group(var_group::Vector{<:VarName}, model::BUGSModel)
 end
 
 function AbstractPPL.evaluate!!(rng::Random.AbstractRNG, model::BUGSModel)
-    (; evaluation_env, g) = model
-    vi = deepcopy(evaluation_env)
     logp = 0.0
+    evaluation_env = deepcopy(model.evaluation_env)
     for (i, vn) in enumerate(model.flattened_graph_node_data.sorted_nodes)
         is_stochastic = model.flattened_graph_node_data.is_stochastic_vals[i]
         node_function = model.flattened_graph_node_data.node_function_vals[i]
@@ -444,7 +443,16 @@ function AbstractPPL.evaluate!!(rng::Random.AbstractRNG, model::BUGSModel)
         else
             dist = node_function(model.evaluation_env, loop_vars)
             value = rand(rng, dist) # just sample from the prior
-            logp += logpdf(dist, value)
+            if model.transformed
+                # see below for why we need to transform the value
+                value_transformed = Bijectors.transform(Bijectors.bijector(dist), value)
+                logp +=
+                    Distributions.logpdf(dist, value) + Bijectors.logabsdetjac(
+                        Bijectors.inverse(Bijectors.bijector(dist)), value_transformed
+                    )
+            else
+                logp += Distributions.logpdf(dist, value)
+            end
             evaluation_env = setindex!!(evaluation_env, value, vn)
         end
     end
@@ -467,6 +475,8 @@ function AbstractPPL.evaluate!!(model::BUGSModel)
             if model.transformed
                 # although the values stored in `evaluation_env` are in their original space, 
                 # here we behave as accepting a vector of parameters in the transformed space
+                # this is so that we have consistent logp values between
+                # (1) set values in original space then evaluate (2) directly evaluate with the values in transformed space 
                 value_transformed = Bijectors.transform(Bijectors.bijector(dist), value)
                 logp +=
                     Distributions.logpdf(dist, value) + Bijectors.logabsdetjac(