ch4

slobodin · Aug 31, 2012 · d470443 · d470443
1 parent a824645
commit d470443
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Showing 6 changed files with 267 additions and 223 deletions.
diff --git a/ch4/interpreter-cpp/schint/expression.cpp b/ch4/interpreter-cpp/schint/expression.cpp
@@ -6,124 +6,75 @@
  */
 
 #include "expression.h"
-#include <algorithm>
+#include "schemelist.h"
+
 #include <stdexcept>
 
-enum ExpressionType
-{
-    Number,
-    Variable,
-    Quote,
-    Assignment,
-    Definition,
-    If,
-    Lambda,
-    Begin,
-    Application
-};
-
-// REDO!!!!!!!!!!!!!!!!! THIS IS XYNTA
-
-class List
-{
-    std::string m_listString;
-
-    static void makeList(std::string &rawStr)
-    {
-        for (size_t i = 0; i < rawStr.size(); i++)
-        {
-            char &ch = rawStr.at(i);
-            if (i != std::string::npos && i != 0)
-            {
-                if (std::isspace(ch))
-                {
-                    const char &prevCh = rawStr.at(i - 1);
-                    const char &nextCh = rawStr.at(i + 1);
-
-                    if (prevCh == '(' || nextCh == ')' || prevCh == ' ' || nextCh == ' ')
-                    {
-                        rawStr.erase(i, 1); i--;
-                    }
-                }
-            }
-        }
-    }
-
-public:
-    List(const std::string &str) : m_listString(str)
-    {
-        if (str.empty() || str[0] != '(' || str[str.size() - 1] != ')')
-            throw std::runtime_error("Bad expression.");
-        makeList(m_listString);
-    }
-
-    ExpressionType type() const
-    {
-        std::string tag = car(*this).string();
-
-        if (tag == "\'")
-            return Quote;
-        if (tag == "set!")
-            return Assignment;
-        if (tag == "define")
-            return Definition;
-        if (tag == "if")
-            return If;
-        if (tag == "lambda")
-            return Lambda;
-        if (tag == "begin")
-            return Begin;
+Expression::Expression()
+{
+}
+
+//Expression::ExpressionType Expression::typeBySExpression(const std::string &sexpr)
+//{
+//    std::string tag = sexpr.substr(1, sexpr.find(' ') - 1);
+
+
+
+//    throw std::runtime_error(std::string("Unknown expression type ") + tag + " .");
+//}
+
+Expression *Expression::analyzeExpression(const std::string &str)
+{
+    SchemeList lst(str);
+
+    std::string tag = lst.car();
+
+    if (tag == "\'")
+        return nullptr;
+    if (tag == "set!")
+        return nullptr;
+    if (tag == "define")
+        return new DefinitionExpression(0 /* analyze (rest) */, 0);
+    if (tag == "if")
+        return nullptr;
+    if (tag == "lambda")
+        return nullptr;
+    if (tag == "begin")
+        return nullptr;
 //        if (tag == number);
 //        if (tag == symbol);
 //        if (tag == pair);
 
-        throw std::runtime_error(std::string("Unknown expression type ") + tag + " .");
-    }
-
-    // REDO!!!!!!!!!!!!!!!!! THIS IS XYNTA
+    throw std::runtime_error(std::string("Unknown expression type ") + tag + " .");
+//    ExpressionType exprType = typeBySExpression(expr);
 
-    static List car(const List &lst)
-    {
-        if (lst.string() == "()" || lst.string().at(0) != '(')
-            throw std::runtime_error("Unable to get car.");
-        return List(lst.string().substr(1, lst.string().find(' ') - 1));
-    }
+//    new DefinitionExpr(cadr(expr), createExpression(caddr(expr)));
 
-    static List cdr(const List &lst)
-    {
-        std::string res = std::string("(") + lst.string().substr(lst.string().find(' '));
-        makeList(res);
-        return List(res);
-    }
+//    if (exprType == Quote)
+//        return new QuotedExpression(List::car(List::cdr(expr)).string());
+//    if (exprType == Assignment)
+//        return new AssignmentExpression("");
+//    if (exprType == Definition)
+//        return new DefinitionExpression("");
+//    if (exprType == If)
+//        return new IfExpression("");
+//    if (exprType == Lambda)
+//        return new LambdaExpression("");
+//    if (exprType == Begin)
+//        return new BeginExpression("");
 
-    std::string string() const { return m_listString; }
-};
+//    return nullptr;
+}
 
-Expression::Expression()
+Expression *Expression::car() const
 {
 }
 
-Expression *Expression::createExpression(const std::string &str)
+Expression *Expression::cdr() const
 {
-    List expr(str);
-    ExpressionType exprType = expr.type();
-
-    if (exprType == Quote)
-        return new QuotedExpression(List::car(List::cdr(expr)).string());
-    if (exprType == Assignment)
-        return new AssignmentExpression("");
-    if (exprType == Definition)
-        return new DefinitionExpression("");
-    if (exprType == If)
-        return new IfExpression("");
-    if (exprType == Lambda)
-        return new LambdaExpression("");
-    if (exprType == Begin)
-        return new BeginExpression("");
-
-    return nullptr;
 }
 
+/*
 VariableExpression::VariableExpression(const std::string &value)
 {
 }
@@ -158,9 +109,9 @@ Expression *AssignmentExpression::eval(Environment *env)
 
 std::string AssignmentExpression::toString() const
 {
-}
+}*/
 
-DefinitionExpression::DefinitionExpression(const std::string &value)
+DefinitionExpression::DefinitionExpression(Expression *variable, Expression *value)
 {
 }
 
@@ -171,7 +122,7 @@ Expression *DefinitionExpression::eval(Environment *env)
 std::string DefinitionExpression::toString() const
 {
 }
-
+/*
 IfExpression::IfExpression(const std::string &value)
 {
 }
@@ -219,3 +170,4 @@ Expression *ApplicationExpression::eval(Environment *env)
 std::string ApplicationExpression::toString() const
 {
 }
+*/