From 17eaadb280fff998ecbd4d6fd526d91d7e34f559 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?L=C3=A9a=20Saviot?= <lea.saviot@numworks.com>
Date: Fri, 9 Nov 2018 14:22:14 +0100
Subject: [PATCH] [poincare] Replace functions when replacing symbols
 iteratively

---
 poincare/include/poincare/function.h |  6 ++++--
 poincare/src/function.cpp            | 13 +++++++++++++
 2 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/poincare/include/poincare/function.h b/poincare/include/poincare/function.h
index 7cb1e0c01..1d2f7c18b 100644
--- a/poincare/include/poincare/function.h
+++ b/poincare/include/poincare/function.h
@@ -38,6 +38,7 @@ private:
   int serialize(char * buffer, int bufferSize, Preferences::PrintFloatMode floatDisplayMode, int numberOfSignificantDigits) const override;
   // Simplification
   Expression shallowReduce(Context & context, Preferences::AngleUnit angleUnit, bool replaceSymbols = true) override;
+  Expression replaceReplaceableSymbols(Context & context) override;
   // Evaluation
   Evaluation<float> approximate(SinglePrecision p, Context& context, Preferences::AngleUnit angleUnit) const override;
   Evaluation<double> approximate(DoublePrecision p, Context& context, Preferences::AngleUnit angleUnit) const override;
@@ -52,7 +53,8 @@ public:
     replaceChildAtIndexInPlace(0, child);
   }
   static Expression UntypedBuilder(const char * name, size_t length, Expression child, Context * context) {
-    // create an expression only if it is not in the context or defined as a function
+    /* Create an expression only if it is not in the context or defined as a
+     * function */
     Function f(name, length, child);
     if (SymbolAbstract::ValidInContext(f, context)) {
       return f;
@@ -60,9 +62,9 @@ public:
     return Expression();
   }
 
-
   Expression replaceSymbolWithExpression(const SymbolAbstract & symbol, const Expression & expression);
   Expression shallowReduce(Context & context, Preferences::AngleUnit angleUnit, bool replaceSymbols = true);
+  Expression replaceReplaceableSymbols(Context & context);
 };
 
 }
diff --git a/poincare/src/function.cpp b/poincare/src/function.cpp
index 8655e91a3..c2b4e3311 100644
--- a/poincare/src/function.cpp
+++ b/poincare/src/function.cpp
@@ -73,6 +73,10 @@ Expression FunctionNode::shallowReduce(Context & context, Preferences::AngleUnit
   return Function(this).shallowReduce(context, angleUnit, replaceSymbols); // This uses Symbol::shallowReduce
 }
 
+Expression FunctionNode::replaceReplaceableSymbols(Context & context) {
+  return Function(this).replaceReplaceableSymbols(context);
+}
+
 Evaluation<float> FunctionNode::approximate(SinglePrecision p, Context& context, Preferences::AngleUnit angleUnit) const {
   return templatedApproximate<float>(context, angleUnit);
 }
@@ -134,4 +138,13 @@ Expression Function::shallowReduce(Context & context, Preferences::AngleUnit ang
   return *this;
 }
 
+Expression Function::replaceReplaceableSymbols(Context & context) {
+  Expression e = context.expressionForSymbol(*this);
+  if (e.isUninitialized()) {
+    return *this;
+  }
+  replaceWithInPlace(e);
+  return e;
+}
+
 }