Modifying emptyset.h and sexpr. Adding SetLanguage.

- Modifies expr/emptyset.h to use SetType only as an incomplete type within expr/emptyset.h. This breaks the include cycle between expr/emptyset.h, expr/expr.h and expr/type.h.
- Refactors SExpr to avoid a potentially infinite cycle. This is likely overkill, but it works.
- Moving Expr::setlanguage and related utilities out of the Expr class and into their own file. This allows files in util/ to know the output language set on an ostream.

4 files changed, 183 insertions, 1 deletions

diff --git a/src/options/Makefile.am b/src/options/Makefile.am
index d871bfb0a..cf38708e1 100644
--- a/src/options/Makefile.am
+++ b/src/options/Makefile.am
@@ -227,6 +227,8 @@ liboptions_la_SOURCES = \
 	printer_modes.h \
 	quantifiers_modes.cpp \
 	quantifiers_modes.h \
+	set_language.cpp \
+	set_language.h \
 	simplification_mode.cpp \
 	simplification_mode.h \
 	theoryof_mode.cpp \
diff --git a/src/options/language.h b/src/options/language.h
index d400b4afb..9191a1d59 100644
--- a/src/options/language.h
+++ b/src/options/language.h
@@ -59,7 +59,7 @@ enum CVC4_PUBLIC Language {
   LANG_Z3STR,
   /** The SyGuS input language */
   LANG_SYGUS,
-  
+
   // START OUTPUT-ONLY LANGUAGES AT ENUM VALUE 10
   // THESE ARE IN PRINCIPLE NOT POSSIBLE INPUT LANGUAGES
 
diff --git a/src/options/set_language.cpp b/src/options/set_language.cpp
new file mode 100644
index 000000000..db0275e04
--- /dev/null
+++ b/src/options/set_language.cpp
@@ -0,0 +1,81 @@
+/*********************                                                        */
+/*! \file language.h
+ ** \verbatim
+ ** Original author: Morgan Deters
+ ** Major contributors: none
+ ** Minor contributors (to current version): Francois Bobot, Andrew Reynolds
+ ** This file is part of the CVC4 project.
+ ** Copyright (c) 2009-2014  New York University and The University of Iowa
+ ** See the file COPYING in the top-level source directory for licensing
+ ** information.\endverbatim
+ **
+ ** \brief Definition of input and output languages
+ **
+ ** Definition of input and output languages.
+ **/
+#include "options/set_language.h"
+
+#include <iosfwd>
+#include <iomanip>
+
+#include "options/language.h"
+#include "options/options.h"
+
+namespace CVC4 {
+namespace language {
+
+const int SetLanguage::s_iosIndex = std::ios_base::xalloc();
+
+SetLanguage::Scope::Scope(std::ostream& out, OutputLanguage language)
+  : d_out(out)
+  , d_oldLanguage(SetLanguage::getLanguage(out))
+{
+  SetLanguage::setLanguage(out, language);
+}
+
+SetLanguage::Scope::~Scope(){
+  SetLanguage::setLanguage(d_out, d_oldLanguage);
+}
+
+
+SetLanguage::SetLanguage(OutputLanguage l)
+  : d_language(l)
+{}
+
+void SetLanguage::applyLanguage(std::ostream& out) {
+  // (offset by one to detect whether default has been set yet)
+  out.iword(s_iosIndex) = int(d_language) + 1;
+}
+
+OutputLanguage SetLanguage::getLanguage(std::ostream& out) {
+  long& l = out.iword(s_iosIndex);
+  if(l == 0) {
+    // set the default language on this ostream
+    // (offset by one to detect whether default has been set yet)
+    if(not Options::isCurrentNull()) {
+      l = options::outputLanguage() + 1;
+    }
+    if(l <= 0 || l > language::output::LANG_MAX) {
+      // if called from outside the library, we may not have options
+      // available to us at this point (or perhaps the output language
+      // is not set in Options).  Default to something reasonable, but
+      // don't set "l" since that would make it "sticky" for this
+      // stream.
+      return OutputLanguage(s_defaultOutputLanguage);
+    }
+  }
+  return OutputLanguage(l - 1);
+}
+
+void SetLanguage::setLanguage(std::ostream& out, OutputLanguage l) {
+  // (offset by one to detect whether default has been set yet)
+  out.iword(s_iosIndex) = int(l) + 1;
+}
+
+std::ostream& operator<<(std::ostream& out, SetLanguage l) {
+  l.applyLanguage(out);
+  return out;
+}
+
+}/* CVC4::language namespace */
+}/* CVC4 namespace */
diff --git a/src/options/set_language.h b/src/options/set_language.h
new file mode 100644
index 000000000..53b0a6a63
--- /dev/null
+++ b/src/options/set_language.h
@@ -0,0 +1,99 @@
+/*********************                                                        */
+/*! \file language.h
+ ** \verbatim
+ ** Original author: Morgan Deters
+ ** Major contributors: none
+ ** Minor contributors (to current version): Francois Bobot, Andrew Reynolds
+ ** This file is part of the CVC4 project.
+ ** Copyright (c) 2009-2014  New York University and The University of Iowa
+ ** See the file COPYING in the top-level source directory for licensing
+ ** information.\endverbatim
+ **
+ ** \brief Definition of input and output languages
+ **
+ ** Definition of input and output languages.
+ **/
+
+#include "cvc4_public.h"
+
+#ifndef __CVC4__OPTIONS__SET_LANGUAGE_H
+#define __CVC4__OPTIONS__SET_LANGUAGE_H
+
+#include <iostream>
+#include "options/language.h"
+
+namespace CVC4 {
+namespace language {
+
+/**
+ * IOStream manipulator to set the output language for Exprs.
+ */
+class CVC4_PUBLIC SetLanguage {
+public:
+  /**
+   * Set a language on the output stream for the current stack scope.
+   * This makes sure the old language is reset on the stream after
+   * normal OR exceptional exit from the scope, using the RAII C++
+   * idiom.
+   */
+  class Scope {
+   public:
+    Scope(std::ostream& out, OutputLanguage language);
+    ~Scope();
+   private:
+    std::ostream& d_out;
+    OutputLanguage d_oldLanguage;
+  };/* class SetLanguage::Scope */
+
+  /**
+   * Construct a ExprSetLanguage with the given setting.
+   */
+  SetLanguage(OutputLanguage l);
+
+  void applyLanguage(std::ostream& out);
+
+  static OutputLanguage getLanguage(std::ostream& out);
+
+  static void setLanguage(std::ostream& out, OutputLanguage l);
+
+private:
+
+  /**
+   * The allocated index in ios_base for our depth setting.
+   */
+  static const int s_iosIndex;
+
+  /**
+   * The default language to use, for ostreams that haven't yet had a
+   * setlanguage() applied to them and where the current Options
+   * information isn't available.
+   */
+  static const int s_defaultOutputLanguage = language::output::LANG_AUTO;
+
+  /**
+   * When this manipulator is used, the setting is stored here.
+   */
+  OutputLanguage d_language;
+};/* class SetLanguage */
+
+
+/**
+ * Sets the output language when pretty-printing a Expr to an ostream.
+ * This is used liek this:
+ *
+ *   // let out be an ostream, e an Expr
+ *   out << language::SetLanguage(LANG_SMTLIB_V2_5) << e << endl;
+ *
+ * This used to be used like this:
+ *
+ *   // let out be an ostream, e an Expr
+ *   out << Expr::setlanguage(LANG_SMTLIB_V2_5) << e << endl;
+ *
+ * The setting stays permanently (until set again) with the stream.
+ */
+std::ostream& operator<<(std::ostream& out, SetLanguage l) CVC4_PUBLIC;
+
+}/* CVC4::language namespace */
+}/* CVC4 namespace */
+
+#endif /* __CVC4__OPTIONS__SET_LANGUAGE_H */