From 401ed2b66c9e80eecaf154f3a2ef932f919ae456 Mon Sep 17 00:00:00 2001
From: Kyle K <kylek389@gmail.com>
Date: Sat, 5 May 2012 23:04:46 -0500
Subject: implement overloaded optrs and outward conversion

---
 main.cpp   | 10 +++++-----
 string.cpp | 37 ++++++++++++++++++++++++++++++++++++-
 string.h   | 11 +++++------
 3 files changed, 46 insertions(+), 12 deletions(-)

diff --git a/main.cpp b/main.cpp
index b951358..dd4810d 100644
--- a/main.cpp
+++ b/main.cpp
@@ -5,24 +5,24 @@ int main(int argc, char **argv)
     MyString mystr("alpha");
     if (mystr.isSubstring("ph"))
     {
-        cout << "true" << endl;
+        std::cout << "true" << std::endl;
     }
     else
-        cout << "false" << endl;
+        std::cout << "false" << std::endl;
 
     MyString mystr1 = ", beta";
     MyString mystr2 = ", charlie";
     MyString mystr3 = ", delta";
 
     mystr.concat(mystr1).concat(mystr2).concat(mystr3);
-    cout << mystr << endl;
+    std::cout << mystr << std::endl;
 
     MyString mystr4 = "hello";
     mystr4.concat(", world!").concat(" goodbye");
-    cout << mystr4 << endl;
+    std::cout << mystr4 << std::endl;
 
     MyString mystr5 = "bro";
-    cout << mystr5 << endl;
+    std::cout << mystr5 << ", char at 1 is: " << mystr5[1] << std::endl;
 
     return 0;
 }
diff --git a/string.cpp b/string.cpp
index 393368f..42e97cc 100644
--- a/string.cpp
+++ b/string.cpp
@@ -139,8 +139,43 @@ bool operator==(const MyString& lhs, const MyString& rhs)
  * but it seems like the & is placed there so we can make consecutive overloaded
  * calls to cout, effectively chaining all of the calls
  */
-ostream& operator<<(ostream& ostr, const MyString& rhs)
+
+/* right now I think the reference is used to avoid returning copy of ostream
+ * so when calls are chained up we work on one ostream object only */
+std::ostream& operator<<(std::ostream& ostr, const MyString& rhs)
 {
     return (ostr << rhs.str_);
 }
 
+/* unary operator operate on one operand, itself! */
+bool MyString::operator!(void) const
+{
+    return (this->length_ == 0);
+}
+
+char& MyString::operator[](int i)
+{
+    /* references need to point to valid objects, all hell could breaks loose */
+    return this->str_[i];
+}
+
+char MyString::operator[](int i) const
+{
+    if (i < 0 || i > this->length_ - 1)
+        return 0;
+    else
+        return this->str_[i];
+}
+
+MyString::operator char*()
+{
+    char *ret = new char[this->length_ + 1];
+    if (ret)
+    {
+        strcpy(ret, this->str_);
+        return ret;
+    }
+    else
+        return NULL;
+}
+
diff --git a/string.h b/string.h
index dc9ebfc..dbc8e88 100644
--- a/string.h
+++ b/string.h
@@ -8,12 +8,10 @@
 #include <cstring>
 #include <iostream>
 
-using namespace std;
-
 class MyString
 {
     friend bool operator==(const MyString&, const MyString &);
-    friend ostream& operator<<(ostream&, const MyString &);
+    friend std::ostream& operator<<(std::ostream&, const MyString &);
 
     private:
         char *str_;
@@ -36,13 +34,14 @@ class MyString
         MyString& concat(const char *);
         void printStr(void) const;
 
-        MyString operator!() const;
+        bool operator!(void) const;
         char& operator[](int);
         char operator[](int) const;
+        operator char*(); /* outward class conversion into char * */
 };
 
 bool operator==(const MyString&, const MyString &);
-ostream& operator<<(ostream&, const MyString &);
+std::ostream& operator<<(std::ostream&, const MyString &);
 
 inline MyString::MyString()
 {
@@ -66,7 +65,7 @@ inline int MyString::length() const
 
 inline void MyString::printStr(void) const
 {
-    cout << "length: " << length_ << ", value: \"" << str_ <<"\"";
+    std::cout << "length: " << length_ << ", value: \"" << str_ << "\"";
 }
 
 #endif
-- 
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