1 files changed, 116 insertions, 0 deletions
diff --git a/Lib/csharp/std_string_view.i b/Lib/csharp/std_string_view.i
new file mode 100644
index 000000000..3b6cd40ef
--- /dev/null
+++ b/Lib/csharp/std_string_view.i
@@ -0,0 +1,116 @@
+/* -----------------------------------------------------------------------------
+ * std_string_view.i
+ *
+ * Typemaps for std::string_view and const std::string_view&
+ * These are mapped to a C# String and are passed around by value.
+ *
+ * To use non-const std::string_view references use the following %apply.  Note
+ * that they are passed by value.
+ * %apply const std::string_view & {std::string_view &};
+ * ----------------------------------------------------------------------------- */
+
+%{
+#include <string_view>
+#include <string>
+%}
+
+namespace std {
+
+%naturalvar string_view;
+
+class string_view;
+
+// string_view
+%typemap(ctype) string_view "const char *"
+%typemap(imtype) string_view "string"
+%typemap(cstype) string_view "string"
+
+%typemap(csdirectorin) string_view "$iminput"
+%typemap(csdirectorout) string_view "$cscall"
+
+%typemap(in, canthrow=1) string_view
+%{ if (!$input) {
+    SWIG_CSharpSetPendingExceptionArgument(SWIG_CSharpArgumentNullException, "null string", 0);
+    return $null;
+   }
+   $1 = std::string_view($input); %}
+%typemap(out) string_view %{ $result = SWIG_csharp_string_callback(std::string($1).c_str()); %}
+
+%typemap(directorout, canthrow=1, warning=SWIGWARN_TYPEMAP_THREAD_UNSAFE_MSG) string_view
+%{ if (!$input) {
+    SWIG_CSharpSetPendingExceptionArgument(SWIG_CSharpArgumentNullException, "null string", 0);
+    return $null;
+   }
+   /* possible thread/reentrant code problem */
+   static std::string $1_str;
+   $1_str = $input;
+   $result = std::string_view($1_str); %}
+
+%typemap(directorin) string_view %{ $input = std::string($1).c_str(); %}
+
+%typemap(csin) string_view "$csinput"
+%typemap(csout, excode=SWIGEXCODE) string_view {
+    string ret = $imcall;$excode
+    return ret;
+  }
+
+%typemap(typecheck) string_view = char *;
+
+%typemap(throws, canthrow=1) string_view
+%{ SWIG_CSharpSetPendingException(SWIG_CSharpApplicationException, std::string($1).c_str());
+   return $null; %}
+
+// const string_view &
+%typemap(ctype) const string_view & "const char *"
+%typemap(imtype) const string_view & "string"
+%typemap(cstype) const string_view & "string"
+
+%typemap(csdirectorin) const string_view & "$iminput"
+%typemap(csdirectorout) const string_view & "$cscall"
+
+%typemap(in, canthrow=1) const string_view &
+%{ if (!$input) {
+    SWIG_CSharpSetPendingExceptionArgument(SWIG_CSharpArgumentNullException, "null string", 0);
+    return $null;
+   }
+   $*1_ltype $1_str($input);
+   $1 = &$1_str; %}
+%typemap(out) const string_view & %{ $result = SWIG_csharp_string_callback(std::string(*$1).c_str()); %}
+
+%typemap(csin) const string_view & "$csinput"
+%typemap(csout, excode=SWIGEXCODE) const string_view & {
+    string ret = $imcall;$excode
+    return ret;
+  }
+
+%typemap(directorout, canthrow=1, warning=SWIGWARN_TYPEMAP_THREAD_UNSAFE_MSG) const string_view &
+%{ if (!$input) {
+    SWIG_CSharpSetPendingExceptionArgument(SWIG_CSharpArgumentNullException, "null string", 0);
+    return $null;
+   }
+   /* possible thread/reentrant code problem */
+   static std::string $1_str;
+   $1_str = $input;
+   static $*1_ltype $1_strview;
+   $1_strview = $1_str;
+   $result = &$1_strview; %}
+
+%typemap(directorin) const string_view & %{ $input = std::string($1).c_str(); %}
+
+%typemap(csvarin, excode=SWIGEXCODE2) const string_view & %{
+    set {
+      $imcall;$excode
+    } %}
+%typemap(csvarout, excode=SWIGEXCODE2) const string_view & %{
+    get {
+      string ret = $imcall;$excode
+      return ret;
+    } %}
+
+%typemap(typecheck) const string_view & = char *;
+
+%typemap(throws, canthrow=1) const string_view &
+%{ SWIG_CSharpSetPendingException(SWIG_CSharpApplicationException, std::string($1).c_str());
+   return $null; %}
+
+}