Appease -Wall

[fur] / templates / program.c

diff --git a/templates/program.c b/templates/program.c
index 73d9334..e2e553b 100644 (file)
--- a/templates/program.c
+++ b/templates/program.c
@@ -14,6 +14,10 @@ union Instance;
 typedef union Instance Instance;
 struct Object;
 typedef struct Object Object;
+struct EnvironmentNode;
+typedef struct EnvironmentNode EnvironmentNode;
+struct Environment;
+typedef struct Environment Environment;
 
 const char* const STRING_LITERAL_LIST[] = {
 {% for string_literal in string_literal_list %}
@@ -38,7 +42,7 @@ enum Type
 union Instance
 {
   bool boolean;
-  Object (*closure)(size_t, Object*);
+  Object (*closure)(Environment*, size_t, Object*);
   int32_t integer;
   const char* string;
 };
@@ -51,16 +55,14 @@ struct Object
 
 const Object TRUE = {
   BOOLEAN,
-  true
+  { true }
 };
 
 const Object FALSE = {
   BOOLEAN,
-  false
+  { false }
 };
 
-struct EnvironmentNode;
-typedef struct EnvironmentNode EnvironmentNode;
 struct EnvironmentNode
 {
   const char* key;
@@ -68,29 +70,36 @@ struct EnvironmentNode
   EnvironmentNode* next;
 };
 
-struct Environment;
-typedef struct Environment Environment;
 struct Environment
 {
+  size_t referenceCount;
+  Environment* parent;
   EnvironmentNode* root;
 };
 
-Environment* Environment_construct()
+Environment* Environment_construct(Environment* parent)
 {
-  // TODO Handle malloc returning NULL
   Environment* result = malloc(sizeof(Environment));
+  result->referenceCount = 1;
+  result->parent = parent;
   result->root = NULL;
   return result;
 }
 
 void Environment_destruct(Environment* self)
 {
-  EnvironmentNode* next;
-  for(EnvironmentNode* node = self->root; node != NULL; node = next)
+  self->referenceCount--;
+
+  if(self->referenceCount == 0)
   {
-    // No objects are allocated on the heap (yet!) so we don't need to free anything else
-    next = node->next;
-    free(node);
+    EnvironmentNode* next;
+    for(EnvironmentNode* node = self->root; node != NULL; node = next)
+    {
+      // No objects are allocated on the heap (yet!) so we don't need to free anything else
+      next = node->next;
+      free(node);
+    }
+    free(self);
   }
 }
 
@@ -115,6 +124,11 @@ Object Environment_get(Environment* self, const char* const symbol)
     }
   }
 
+  if(self->parent != NULL)
+  {
+    return Environment_get(self->parent, symbol);
+  }
+
   // TODO Handle symbol errors
   assert(false);
 }
@@ -206,7 +220,7 @@ Object operator$equals(Object left, Object right)
   assert(left.type == INTEGER);
   assert(right.type == INTEGER);
 
-  Object result = { BOOLEAN, left.instance.integer == right.instance.integer };
+  Object result = { BOOLEAN, { left.instance.integer == right.instance.integer } };
   return result;
 }
 
@@ -215,7 +229,7 @@ Object operator$notEquals(Object left, Object right)
   assert(left.type == INTEGER);
   assert(right.type == INTEGER);
 
-  Object result = { BOOLEAN, left.instance.integer != right.instance.integer };
+  Object result = { BOOLEAN, { left.instance.integer != right.instance.integer } };
   return result;
 }
 
@@ -224,7 +238,7 @@ Object operator$greaterThan(Object left, Object right)
   assert(left.type == INTEGER);
   assert(right.type == INTEGER);
 
-  Object result = { BOOLEAN, left.instance.integer > right.instance.integer };
+  Object result = { BOOLEAN, { left.instance.integer > right.instance.integer } };
   return result;
 }
 
@@ -233,7 +247,7 @@ Object operator$lessThan(Object left, Object right)
   assert(left.type == INTEGER);
   assert(right.type == INTEGER);
 
-  Object result = { BOOLEAN, left.instance.integer < right.instance.integer };
+  Object result = { BOOLEAN, { left.instance.integer < right.instance.integer } };
   return result;
 }
 
@@ -242,7 +256,7 @@ Object operator$greaterThanOrEqual(Object left, Object right)
   assert(left.type == INTEGER);
   assert(right.type == INTEGER);
 
-  Object result = { BOOLEAN, left.instance.integer >= right.instance.integer };
+  Object result = { BOOLEAN, { left.instance.integer >= right.instance.integer } };
   return result;
 }
 
@@ -251,7 +265,7 @@ Object operator$lessThanOrEqual(Object left, Object right)
   assert(left.type == INTEGER);
   assert(right.type == INTEGER);
 
-  Object result = { BOOLEAN, left.instance.integer <= right.instance.integer };
+  Object result = { BOOLEAN, { left.instance.integer <= right.instance.integer } };
   return result;
 }
 
@@ -260,7 +274,7 @@ Object operator$and(Object left, Object right)
   assert(left.type == BOOLEAN);
   assert(right.type == BOOLEAN);
 
-  Object result = { BOOLEAN, left.instance.boolean && right.instance.boolean };
+  Object result = { BOOLEAN, { left.instance.boolean && right.instance.boolean } };
   return result;
 }
 
@@ -269,12 +283,12 @@ Object operator$or(Object left, Object right)
   assert(left.type == BOOLEAN);
   assert(right.type == BOOLEAN);
 
-  Object result = { BOOLEAN, left.instance.boolean || right.instance.boolean };
+  Object result = { BOOLEAN, { left.instance.boolean || right.instance.boolean } };
   return result;
 }
 
 {% if 'pow' in builtins %}
-Object builtin$pow$implementation(size_t argc, Object* args)
+Object builtin$pow$implementation(Environment* parent, size_t argc, Object* args)
 {
   assert(argc == 2);
 
@@ -294,7 +308,7 @@ Object builtin$pow = { CLOSURE, (Instance)builtin$pow$implementation };
 {% endif %}
 
 {% if 'print' in builtins %}
-Object builtin$print$implementation(size_t argc, Object* args)
+Object builtin$print$implementation(Environment* parent, size_t argc, Object* args)
 {
   for(size_t i = 0; i < argc; i++)
   {
@@ -327,11 +341,11 @@ Object builtin$print = { CLOSURE, (Instance)builtin$print$implementation };
 {% endif %}
 
 {% for function_definition in function_definition_list %}
-Object user${{function_definition.name}}$implementation(size_t argc, Object* args)
+Object user${{function_definition.name}}$implementation(Environment* parent, size_t argc, Object* args)
 {
-  Environment* environment = Environment_construct();
+  Environment* environment = Environment_construct(parent);
 
-  {% for statement in function_definition.statement_list %}
+  {% for statement in function_definition.statement_list[:-1] %}
   {{ generate_statement(statement) }}
   {% endfor %}
 
@@ -345,7 +359,7 @@ Object user${{function_definition.name}} = { CLOSURE, (Instance)user${{function_
 
 int main(int argc, char** argv)
 {
-  Environment* environment = Environment_construct();
+  Environment* environment = Environment_construct(NULL);
 
   // TODO Use the symbol from SYMBOL_LIST
   {% for builtin in builtins %}