From 76ac7c36fec81b164768a75bfb9446efd6faca4f Mon Sep 17 00:00:00 2001
From: Jason Turner <jason@emptycrate.com>
Date: Sat, 31 Jan 2015 07:28:37 -0700
Subject: [PATCH] Simplify redundant bool condition checking

---
 CMakeLists.txt                                |  2 +-
 .../chaiscript/language/chaiscript_common.hpp |  9 +++++
 .../chaiscript/language/chaiscript_eval.hpp   | 36 ++++---------------
 3 files changed, 17 insertions(+), 30 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 36b5698..f942eb0 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -152,7 +152,7 @@ if(MSVC)
   # how to workaround or fix the error. So I'm disabling it globally.
   add_definitions(/wd4503)
 else()
-  add_definitions(-Wall -Wextra -Wshadow -Wnon-virtual-dtor -Wold-style-cast -Wcast-align -Wcast-qual -Woverloaded-virtual  -pedantic ${CPP11_FLAG})
+  add_definitions(-Wall -Wextra -Wshadow -Wnon-virtual-dtor -Wold-style-cast -Wcast-align -Wcast-qual -Wunused -Woverloaded-virtual  -pedantic ${CPP11_FLAG})
 
   if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang")
     add_definitions(-Weverything -Wno-c++98-compat -Wno-documentation -Wno-switch-enum -Wno-weak-vtables -Wno-sign-conversion -Wno-missing-prototypes -Wno-padded -Wno-missing-noreturn)
diff --git a/include/chaiscript/language/chaiscript_common.hpp b/include/chaiscript/language/chaiscript_common.hpp
index e383d16..1a920bd 100644
--- a/include/chaiscript/language/chaiscript_common.hpp
+++ b/include/chaiscript/language/chaiscript_common.hpp
@@ -451,6 +451,15 @@ namespace chaiscript
         }
       }
 
+      static bool get_bool_condition(const Boxed_Value &t_bv) {
+        try {
+          return boxed_cast<bool>(t_bv);
+        }
+        catch (const exception::bad_boxed_cast &) {
+          throw exception::eval_error("Condition not boolean");
+        }
+      }
+
 
       void replace_child(const AST_NodePtr &t_child, const AST_NodePtr &t_new_child)
       {
diff --git a/include/chaiscript/language/chaiscript_eval.hpp b/include/chaiscript/language/chaiscript_eval.hpp
index 33477d8..21bb77a 100644
--- a/include/chaiscript/language/chaiscript_eval.hpp
+++ b/include/chaiscript/language/chaiscript_eval.hpp
@@ -826,7 +826,7 @@ namespace chaiscript
           chaiscript::eval::detail::Scope_Push_Pop spp(t_ss);
 
           try {
-            while (boxed_cast<bool>(this->children[0]->eval(t_ss))) {
+            while (get_bool_condition(this->children[0]->eval(t_ss))) {
               try {
                 this->children[1]->eval(t_ss);
               } catch (detail::Continue_Loop &) {
@@ -835,8 +835,6 @@ namespace chaiscript
                 // the next condition test
               }
             } 
-          } catch (const exception::bad_boxed_cast &) {
-            throw exception::eval_error("While condition not boolean");
           } catch (detail::Break_Loop &) {
             // loop was broken intentionally
           }
@@ -868,21 +866,15 @@ namespace chaiscript
           AST_Node(t_ast_node_text, AST_Node_Type::If, t_fname, t_start_line, t_start_col, t_end_line, t_end_col) { }
         virtual ~Ternary_Cond_AST_Node() {}
         virtual Boxed_Value eval_internal(chaiscript::detail::Dispatch_Engine &t_ss) const CHAISCRIPT_OVERRIDE{
-          bool cond = false;
-          try {
-            cond = boxed_cast<bool>(this->children[0]->eval(t_ss));
-          }
-          catch (const exception::bad_boxed_cast &) {
-            throw exception::eval_error("Ternary if condition not boolean");
-          }
 
-          if (cond) {
+          if (get_bool_condition(this->children[0]->eval(t_ss))) {
             return this->children[1]->eval(t_ss);
           }
           else {
             return this->children[2]->eval(t_ss);
           }
         }
+
     };
 
     struct If_AST_Node : public AST_Node {
@@ -891,31 +883,20 @@ namespace chaiscript
           AST_Node(t_ast_node_text, AST_Node_Type::If, t_fname, t_start_line, t_start_col, t_end_line, t_end_col) { }
         virtual ~If_AST_Node() {}
         virtual Boxed_Value eval_internal(chaiscript::detail::Dispatch_Engine &t_ss) const CHAISCRIPT_OVERRIDE{
-          bool cond = false;
-          try {
-            cond = boxed_cast<bool>(this->children[0]->eval(t_ss));
-          }
-          catch (const exception::bad_boxed_cast &) {
-            throw exception::eval_error("If condition not boolean");
-          }
 
-          if (cond) {
+          if (get_bool_condition(this->children[0]->eval(t_ss))) {
             return this->children[1]->eval(t_ss);
           }
           else {
             if (this->children.size() > 2) {
               size_t i = 2;
+              bool cond = false;
               while ((!cond) && (i < this->children.size())) {
                 if (this->children[i]->text == "else") {
                   return this->children[i+1]->eval(t_ss);
                 }
                 else if (this->children[i]->text == "else if") {
-                  try {
-                    cond = boxed_cast<bool>(this->children[i+1]->eval(t_ss));
-                  }
-                  catch (const exception::bad_boxed_cast &) {
-                    throw exception::eval_error("'else if' condition not boolean");
-                  }
+                  cond = get_bool_condition(this->children[i+1]->eval(t_ss));
                   if (cond) {
                     return this->children[i+2]->eval(t_ss);
                   }
@@ -944,7 +925,7 @@ namespace chaiscript
 
           try {
             // while condition evals to true
-            while (boxed_cast<bool>(this->children[1]->eval(t_ss))) {
+            while (get_bool_condition(this->children[1]->eval(t_ss))) {
               try {
                 // Body of Loop
                 this->children[3]->eval(t_ss);
@@ -958,9 +939,6 @@ namespace chaiscript
               this->children[2]->eval(t_ss);
             }
           }
-          catch (const exception::bad_boxed_cast &) {
-            throw exception::eval_error("For condition not boolean");
-          }
           catch (detail::Break_Loop &) {
             // loop broken
           }