From ea39cd3c8c4e7aa70dd9cb3d902a3bdf87737472 Mon Sep 17 00:00:00 2001
From: Yashwant <yashwantsingh.sngh@gmail.com>
Date: Tue, 6 Oct 2020 21:08:37 +0530
Subject: [PATCH] Fix R documentation.

---
 src/mlpack/bindings/R/print_R.cpp              |  3 ++-
 .../bindings/R/print_doc_functions_impl.hpp    | 18 ++++++++++--------
 2 files changed, 12 insertions(+), 9 deletions(-)

diff --git a/src/mlpack/bindings/R/print_R.cpp b/src/mlpack/bindings/R/print_R.cpp
index bf047c2769..5b089cbd28 100644
--- a/src/mlpack/bindings/R/print_R.cpp
+++ b/src/mlpack/bindings/R/print_R.cpp
@@ -92,7 +92,8 @@ void PrintR(const util::BindingDetails& doc,
   cout << "#'" << endl;
 
   // Next, print information on the output options.
-  cout << "#' @return A list with several components:" << endl;
+  if (outputOptions.size() > 0)
+    cout << "#' @return A list with several components:" << endl;
 
   for (size_t i = 0; i < outputOptions.size(); ++i)
   {
diff --git a/src/mlpack/bindings/R/print_doc_functions_impl.hpp b/src/mlpack/bindings/R/print_doc_functions_impl.hpp
index 2273f83197..dcdfd5d15d 100644
--- a/src/mlpack/bindings/R/print_doc_functions_impl.hpp
+++ b/src/mlpack/bindings/R/print_doc_functions_impl.hpp
@@ -61,10 +61,10 @@ inline std::string PrintValue(const T& value, bool quotes)
 {
   std::ostringstream oss;
   if (quotes)
-    oss << "\"";
+    oss << "`";
   oss << value;
   if (quotes)
-    oss << "\"";
+    oss << "`";
   return oss.str();
 }
 
@@ -76,7 +76,7 @@ inline std::string PrintValue(const std::vector<T>& value, bool quotes)
 {
   std::ostringstream oss;
   if (quotes)
-    oss << "\"";
+    oss << "`";
   oss << "c(";
   if (value.size() > 0)
   {
@@ -86,7 +86,7 @@ inline std::string PrintValue(const std::vector<T>& value, bool quotes)
   }
   oss << ")";
   if (quotes)
-    oss << "\"";
+    oss << "`";
   return oss.str();
 }
 
@@ -229,7 +229,9 @@ std::string ProgramCall(const bool markdown,
 
   // Find out if we have any output options first.
   std::ostringstream ossOutput;
-  oss << "output <- ";
+  ossOutput << PrintOutputOptions(markdown, args...);
+  if (ossOutput.str() != "")
+    oss << "output <- ";
   oss << programName << "(";
 
   // Now process each input option.
@@ -330,7 +332,7 @@ inline std::string ProgramCall(const std::string& programName)
  */
 inline std::string PrintModel(const std::string& modelName)
 {
-  return "\"" + modelName + "\"";
+  return "`" + modelName + "`";
 }
 
 /**
@@ -339,7 +341,7 @@ inline std::string PrintModel(const std::string& modelName)
  */
 inline std::string PrintDataset(const std::string& datasetName)
 {
-  return "\"" + datasetName + "\"";
+  return "`" + datasetName + "`";
 }
 
 /**
@@ -357,7 +359,7 @@ inline std::string ProgramCallClose()
 inline std::string ParamString(const std::string& paramName)
 {
   // For a R binding we don't need to know the type.
-  return "\"" + paramName + "\"";
+  return "`" + paramName + "`";
 }
 
 /**