diff --git a/src/codegen.cpp b/src/codegen.cpp
index 3d685fd..7a13f71 100644
--- a/src/codegen.cpp
+++ b/src/codegen.cpp
@@ -136,6 +136,7 @@ private:
   const char* getSourceBaseType(llvm::Type* type);
   std::string getSourceType(llvm::Type* type);
 
+  llvm::Value* evalBooleanCondition(const Expression* condition_expression);
   llvm::Value* evalTruthiness(llvm::Value* val);
 
   llvm::Function* current_function() { return builder_.GetInsertBlock()->getParent(); }
@@ -329,6 +330,17 @@ llvm::Value* IRGenerator::visitAssignStatement(const AssignStatement* a) {
   return nullptr;
 }
 
+llvm::Value* IRGenerator::evalBooleanCondition(const Expression* condition_expression) {
+  llvm::Value* condition = visit(condition_expression);
+  auto condition_type = condition->getType();
+  condition = evalTruthiness(condition);
+  if (!condition) {
+    error(condition_expression, "cannot convert expression of type",
+          getSourceType(condition_type), "to boolean.");
+  }
+  return condition;
+}
+
 llvm::Value* IRGenerator::evalTruthiness(llvm::Value* val) {
   if (llvm::isa<llvm::CmpInst>(val)) return val;
   auto val_type = val->getType();
@@ -354,13 +366,8 @@ llvm::Value* IRGenerator::visitBranchStatement(const BranchStatement* b) {
   builder_.SetInsertPoint(case_cond_bb);
 
   for (const BranchCase& branch_case : b->cases()) {
-    llvm::Value* condition = visit(branch_case.getExpression());
-    auto condition_type = condition->getType();
-    condition = evalTruthiness(condition);
-    if (!condition) {
-      error(branch_case.getExpression(), "cannot convert expression of type",
-            getSourceType(condition_type), "to boolean.");
-    }
+    llvm::Value* condition = evalBooleanCondition(branch_case.getExpression());
+
     case_cond_bb = llvm::BasicBlock::Create(context_, "branch.case.cond");
     llvm::BasicBlock* case_body_bb =
         llvm::BasicBlock::Create(context_, "branch.case.body", current_function());
@@ -411,13 +418,7 @@ llvm::Value* IRGenerator::visitLoopStatement(const LoopStatement* l) {
 
   builder_.CreateBr(condition_bb);
   builder_.SetInsertPoint(condition_bb);
-  auto condition = visit(l->getCondition());
-  auto condition_type = condition->getType();
-  condition = evalTruthiness(condition);
-  if (!condition) {
-    error(l->getCondition(), "cannot convert expression of type", getSourceType(condition_type),
-          "to boolean");
-  }
+  llvm::Value* condition = evalBooleanCondition(l->getCondition());
   builder_.CreateCondBr(condition, body_bb, after_bb);
 
   current_function()->getBasicBlockList().push_back(after_bb);