Add Slang::String compatibility with std::ostream (#2256)

* Work around MacOS compilation issue with embed stlib

- The enable-stdlib-generator project is created with
  'kind = StaticLib' to allow the build to work, even though
  the project doesn't actually create a library.

- Unlike some other platforms, MacOs "ar" emits an error if no
  object files are listed to be added to an archive. This causes
  enable-stdlib-generator to fail on MacOS.

- Changing the project's kind to "SharedLib" works around the issue.
  Other values for kind do not seem to work around the issue.

- Add an optional flag to generatorProject to indicate that
  kind = "SharedLibrary" should be used, rather than "StaticLibrary"

- Enable embed stdlib in github_macos_build.sh

* Allow Strings to be used with std::ostream.

Co-authored-by: jsmall-nvidia <jsmall@nvidia.com>

2 files changed, 9 insertions, 0 deletions

diff --git a/source/core/slang-string.cpp b/source/core/slang-string.cpp
index 1a6221cc8..5f2ba13ba 100644
--- a/source/core/slang-string.cpp
+++ b/source/core/slang-string.cpp
@@ -690,5 +690,10 @@ namespace Slang
 
         return true;
     }
+}
 
+std::ostream& operator<< (std::ostream& stream, const Slang::String& s)
+{
+    stream << s.getBuffer();
+    return stream;
 }
diff --git a/source/core/slang-string.h b/source/core/slang-string.h
index 5119dac8f..e8ee76397 100644
--- a/source/core/slang-string.h
+++ b/source/core/slang-string.h
@@ -4,6 +4,7 @@
 #include <string.h>
 #include <cstdlib>
 #include <stdio.h>
+#include <iostream>
 
 #include "slang-smart-pointer.h"
 #include "slang-common.h"
@@ -1038,6 +1039,7 @@ namespace Slang
             length -= actualDelLength;
         }
 #endif
+        friend std::ostream& operator<< (std::ostream& stream, const String& s);
 
         void Clear()
         {
@@ -1051,4 +1053,6 @@ namespace Slang
     float StringToFloat(const String & str);
 }
 
+std::ostream& operator<< (std::ostream& stream, const Slang::String& s);
+
 #endif