Update functions to use the clone interface.

Change-Id: I6b4d6be5b1d963bc7d97851432e40844d3619d8d

poincare/include/poincare/cosinus.h

@@ -5,9 +5,10 @@
 
 class Cosinus : public Function {
   public:
-    Cosinus(Expression * arg): Function(arg, (char*) "cos") {}
+    Cosinus(Expression * arg, bool clone_arg=true): Function(arg, (char*) "cos", clone_arg) {}
     float approximate(Context& context) override;
     Type type() override;
+    Expression * clone() override;
 };
 
 #endif

poincare/include/poincare/function.h

@@ -5,9 +5,11 @@
 
 class Function : public Expression {
   public:
-    Function(Expression * arg, char* function_name): m_arg(arg), m_function_name(function_name) {}
+    Function(Expression * arg, char* function_name, bool clone_operands=true);
     ~Function();
     ExpressionLayout * createLayout(ExpressionLayout * parent) override;
+    Expression * operand(int i) override;
+    int numberOfOperands() override;
   protected:
     Expression * m_arg;
   private:

poincare/include/poincare/sinus.h

@@ -5,9 +5,10 @@
 
 class Sinus : public Function {
   public:
-    Sinus(Expression * arg): Function(arg, (char*) "sin") {}
+    Sinus(Expression * arg, bool clone_arg=true): Function(arg, (char*) "sin", clone_arg) {}
     float approximate(Context& context) override;
     Type type() override;
+    Expression * clone() override;
 };
 
 #endif

poincare/include/poincare/tangent.h

@@ -5,9 +5,10 @@
 
 class Tangent : public Function {
   public:
-    Tangent(Expression * arg): Function(arg, (char*) "tan") {}
+    Tangent(Expression * arg, bool clone_arg=true): Function(arg, (char*) "tan", clone_arg) {}
     float approximate(Context& context) override;
     Type type() override;
+    Expression * clone() override;
 };
 
 #endif

poincare/src/cosinus.cpp

@@ -1,6 +1,10 @@
 #include <poincare/cosinus.h>
 #include "layout/horizontal_layout.h"
 
+Expression * Cosinus::clone() {
+  return new Cosinus(m_arg, true);
+}
+
 Expression::Type Cosinus::type() {
   return Expression::Type::Cosinus;
 }

poincare/src/function.cpp

@@ -1,6 +1,19 @@
+extern "C" {
+#include <stdlib.h>
+}
 #include <poincare/function.h>
 #include "layout/function_layout.h"
 
+Function::Function(Expression * arg, char* function_name, bool clone_operands) {
+  m_arg = (Expression *)malloc(sizeof(Expression));
+  m_function_name = function_name;
+  if (clone_operands) {
+    m_arg = arg->clone();
+  } else {
+    m_arg = arg;
+  }
+}
+
 Function::~Function() {
   delete m_arg;
 }
@@ -8,3 +21,15 @@ Function::~Function() {
 ExpressionLayout * Function::createLayout(ExpressionLayout * parent) {
   return new FunctionLayout(parent, m_function_name, m_arg);
 }
+
+Expression * Function::operand(int i) {
+  if (i==0) {
+    return m_arg;
+  } else {
+    return nullptr;
+  }
+}
+
+int Function::numberOfOperands() {
+  return 1;
+}

poincare/src/sinus.cpp

@@ -1,6 +1,10 @@
 #include <poincare/sinus.h>
 #include "layout/horizontal_layout.h"
 
+Expression * Sinus::clone() {
+  return new Sinus(m_arg, true);
+}
+
 Expression::Type Sinus::type() {
   return Expression::Type::Sinus;
 }

poincare/src/tangent.cpp

@@ -1,6 +1,10 @@
 #include <poincare/tangent.h>
 #include "layout/horizontal_layout.h"
 
+Expression * Tangent::clone() {
+  return new Tangent(m_arg, true);
+}
+
 Expression::Type Tangent::type() {
   return Expression::Type::Tangent;
 }