Offer non-echoing process().

include/cling/Interpreter/Interpreter.h

@@ -447,11 +447,13 @@ namespace cling {
     ///       initialized to point to the return value's location if the
     ///       expression result is an aggregate.
     ///\param[out] T - The cling::Transaction of the compiled input.
+    ///\param[in] disableValuePrinting - Whether to echo the expression result.
     ///
     ///\returns Whether the operation was fully successful.
     ///
     CompilationResult process(const std::string& input, Value* V = 0,
-                              Transaction** T = 0);
+                              Transaction** T = 0,
+                              bool disableValuePrinting = false);
 
     ///\brief Parses input line, which doesn't contain statements. No code
     /// generation is done.

include/cling/MetaProcessor/MetaProcessor.h

@@ -101,12 +101,14 @@ namespace cling {
       return prev;
     }
 
-    ///\brief Process the input coming from the prompt and possibli returns
-    /// result of the execution of the last statement
+    ///\brief Process the input coming from the prompt and possibly returns
+    /// result of the execution of the last statement.
     /// @param[in] input_line - the user input
+    /// @param[out] compRes - whether compilation was successful
     /// @param[out] result - the cling::Value as result of the
     ///             execution of the last statement
-    /// @param[out] compRes - whether compilation was successful
+    /// @param[in] disableValuePrinting - whether to suppress echoing of the
+    ///             expression result
     ///
     ///\returns 0 on success or the indentation of the next input line should
     /// have in case of multi input mode.
@@ -114,7 +116,8 @@ namespace cling {
     ///
     int process(const char* input_line,
                 Interpreter::CompilationResult& compRes,
-                cling::Value* result = nullptr);
+                cling::Value* result = nullptr,
+                bool disableValuePrinting = false);
 
     ///\brief When continuation is requested, this cancels and ignores previous
     /// input, resetting the continuation to a new line.

lib/Interpreter/Interpreter.cpp

@@ -596,7 +596,8 @@ namespace cling {
   ///
   Interpreter::CompilationResult
   Interpreter::process(const std::string& input, Value* V /* = 0 */,
-                       Transaction** T /* = 0 */) {
+                       Transaction** T /* = 0 */,
+                       bool disableValuePrinting /* = false*/) {
     std::string wrapReadySource = input;
     size_t wrapPoint = std::string::npos;
     if (!isRawInputEnabled())
@@ -612,7 +613,8 @@ namespace cling {
 
     CompilationOptions CO = makeDefaultCompilationOpts();
     CO.DeclarationExtraction = 1;
-    CO.ValuePrinting = CompilationOptions::VPAuto;
+    CO.ValuePrinting = disableValuePrinting ? CompilationOptions::VPDisabled
+      : CompilationOptions::VPAuto;
     CO.ResultEvaluation = (bool)V;
     // CO.IgnorePromptDiags = 1; done by EvaluateInternal().
     CO.CheckPointerValidity = 1;

lib/MetaProcessor/MetaProcessor.cpp

@@ -293,7 +293,8 @@ namespace cling {
 
   int MetaProcessor::process(const char* input_text,
                              Interpreter::CompilationResult& compRes,
-                             Value* result) {
+                             Value* result,
+                             bool disableValuePrinting /* = false */) {
     if (result)
       *result = Value();
     compRes = Interpreter::kSuccess;
@@ -337,7 +338,8 @@ namespace cling {
     // if (m_Options.RawInput)
     //   compResLocal = m_Interp.declare(input);
     // else
-    compRes = m_Interp.process(input, result);
+    compRes = m_Interp.process(input, result, /*Transaction*/ nullptr,
+                               disableValuePrinting);
 
     return 0;
   }