diff --git a/poincare/include/poincare/symbol_abstract.h b/poincare/include/poincare/symbol_abstract.h
index 32812f698..2c32368f5 100644
--- a/poincare/include/poincare/symbol_abstract.h
+++ b/poincare/include/poincare/symbol_abstract.h
@@ -43,6 +43,8 @@ protected:
 class SymbolAbstract : public Expression {
 public:
   const char * name() const { return node()->name(); }
+  static size_t TruncateExtension(char * dst, const char * src, size_t len);
+  constexpr static size_t k_maxNameSize = 16;
 protected:
   SymbolAbstract(const SymbolAbstractNode * node) : Expression(node) {}
   SymbolAbstractNode * node() const { return static_cast<SymbolAbstractNode *>(Expression::node()); }
diff --git a/poincare/src/symbol_abstract.cpp b/poincare/src/symbol_abstract.cpp
index f809dc1a0..8525aaa7b 100644
--- a/poincare/src/symbol_abstract.cpp
+++ b/poincare/src/symbol_abstract.cpp
@@ -20,4 +20,14 @@ void SymbolAbstractNode::initName(size_t nameSize) {
   modifiableName[nameSize-1] = 0;
 }
 
+size_t SymbolAbstract::TruncateExtension(char * dst, const char * src, size_t len) {
+  const char * cur = src;
+  const char * end = src+len-1;
+  while (*cur != '.' && cur < end) {
+    *dst++ = *cur++;
+  }
+  *dst = 0;
+  return cur-src;
+}
+
 }