From f6ba746b03eaf54f13e75ad76d9bf298c1b14509 Mon Sep 17 00:00:00 2001
From: Leonardo de Moura <leonardo@microsoft.com>
Date: Fri, 20 Nov 2015 08:55:44 -0800
Subject: [PATCH] chore(library/blast/trace): fix signature

---
 src/library/blast/trace.cpp | 2 +-
 src/library/blast/trace.h   | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/library/blast/trace.cpp b/src/library/blast/trace.cpp
index ffcce70a6..60c91abc4 100644
--- a/src/library/blast/trace.cpp
+++ b/src/library/blast/trace.cpp
@@ -56,7 +56,7 @@ scope_trace::~scope_trace() {
     g_trace = m_old;
 }
 
-io_state_stream & operator<<(io_state_stream & out, ppb const & e) {
+io_state_stream const & operator<<(io_state_stream const & out, ppb const & e) {
     expr tmp = curr_state().to_kernel_expr(e.m_expr);
     out << tmp;
     return out;
diff --git a/src/library/blast/trace.h b/src/library/blast/trace.h
index d6c060b54..b19493846 100644
--- a/src/library/blast/trace.h
+++ b/src/library/blast/trace.h
@@ -30,5 +30,5 @@ struct ppb {
     explicit ppb(expr const & e):m_expr(e) {}
 };
 
-io_state_stream & operator<<(io_state_stream & out, ppb const & e);
+io_state_stream const & operator<<(io_state_stream const & out, ppb const & e);
 }}