diff --git a/iwyu_output.cc b/iwyu_output.cc
index e67474c..3f364ac 100644
--- a/iwyu_output.cc
+++ b/iwyu_output.cc
@@ -457,25 +457,24 @@ string MungedForwardDeclareLineForTemplates(const TemplateDecl* decl) {
   raw_string_ostream ostream(line);
   decl->print(ostream);   // calls DeclPrinter
   line = ostream.str();
+
+  // Remove "final" specifier which isn't needed for forward
+  // declarations.
+  ReplaceAll(&line, " final ", " ");
+
   // Get rid of the superclasses, if any (this will nix the body too).
   line = Split(line, " :", 2)[0];
   // Get rid of the template body, if any (true if no superclasses).
   line = Split(line, " {", 2)[0];
 
-  // Remove "final" specifier which isn't needed for forward
-  // declarations.
-  const char kFinalSpecifier[] = " final ";
-  string::size_type final_pos = line.find(kFinalSpecifier);
-  if (final_pos != string::npos) {
-    line.replace(final_pos, sizeof(kFinalSpecifier), " ");
-  }
-
   // The template name is now the last word on the line.  Replace it
   // by its fully-qualified form.
   const string::size_type name = line.rfind(' ');
   CHECK_(name != string::npos && "Unexpected printable template-type");
 
-  return PrintForwardDeclare(decl, line.substr(0, name), GlobalFlags().cxx17ns);
+  line = line.substr(0, name);
+
+  return PrintForwardDeclare(decl, line, GlobalFlags().cxx17ns);
 }
 
 string MungedForwardDeclareLine(const NamedDecl* decl) {
diff --git a/iwyu_string_util.h b/iwyu_string_util.h
index 78c2dc7..71e4d56 100644
--- a/iwyu_string_util.h
+++ b/iwyu_string_util.h
@@ -119,6 +119,14 @@ inline void StripWhiteSpace(string* str) {
   StripWhiteSpaceRight(str);
 }
 
+inline void ReplaceAll(std::string* str, const std::string& from,
+                       const std::string& to) {
+  for (size_t pos = str->find(from); pos != std::string::npos;
+       pos = str->find(from, pos + to.length())) {
+    str->replace(pos, from.length(), to);
+  }
+}
+
 // This is the same as split() in Python.  If max_segs is 0, there's
 // no limit on the number of the generated segments.
 inline vector<string> Split(