Support cout << error

README.md

@@ -179,7 +179,7 @@ if (!parser.allocate_capacity(1024*1024)) { exit(1); }
 for (padded_string json : { string("[1, 2, 3]"), string("true"), string("[ true, false ]") }) {
   cout << "Parsing " << json.data() << " ..." << endl;
   auto [doc, error] = parser.parse(json);
-  if (error) { cerr << "Error: " << error_message(error) << endl; exit(1); }
+  if (error) { cerr << "Error: " << error << endl; exit(1); }
   doc.print_json(cout);
   cout << endl;
 }

amalgamation.sh

@@ -132,7 +132,7 @@ int main(int argc, char *argv[]) {
   if (error) {
     std::cout << "parse failed" << std::endl;
     std::cout << "error code: " << error << std::endl;
-    std::cout << error_message(error) << std::endl;
+    std::cout << error << std::endl;
   } else {
     std::cout << "parse valid" << std::endl;
   }
@@ -150,7 +150,7 @@ int main(int argc, char *argv[]) {
   if (error) {
     std::cout << "parse_many failed" << std::endl;
     std::cout << "error code: " << error << std::endl;
-    std::cout << error_message(error) << std::endl;
+    std::cout << error << std::endl;
   } else {
     std::cout << "parse_many valid" << std::endl;
   }

benchmark/parse_stream.cpp

@@ -96,7 +96,7 @@ int main (int argc, char *argv[]){
                     batch_size_res[i] = speedinGBs;
 
                 if (error != simdjson::SUCCESS) {
-                    std::wcerr << "Parsing failed with: " << simdjson::error_message(error) << std::endl;
+                    std::wcerr << "Parsing failed with: " << error << std::endl;
                     exit(1);
                 }
             }
@@ -132,7 +132,7 @@ int main (int argc, char *argv[]){
             res.push_back(secs.count());
 
             if (error != simdjson::SUCCESS) {
-                std::wcerr << "Parsing failed with: " << simdjson::error_message(error) << std::endl;
+                std::wcerr << "Parsing failed with: " << error << std::endl;
                 exit(1);
             }
 

include/simdjson/document.h

@@ -949,7 +949,7 @@ public:
    *
    *   document::parser parser;
    *   for (auto [doc, error] : parser.parse_many(buf, len)) {
-   *     if (error) { cerr << error_message(error) << endl; exit(1); }
+   *     if (error) { cerr << error << endl; exit(1); }
    *     cout << std::string(doc["title"]) << endl;
    *   }
    *
@@ -1011,7 +1011,7 @@ public:
    *
    *   document::parser parser;
    *   for (auto [doc, error] : parser.parse_many(buf, len)) {
-   *     if (error) { cerr << error_message(error) << endl; exit(1); }
+   *     if (error) { cerr << error << endl; exit(1); }
    *     cout << std::string(doc["title"]) << endl;
    *   }
    *
@@ -1073,7 +1073,7 @@ public:
    *
    *   document::parser parser;
    *   for (auto [doc, error] : parser.parse_many(buf, len)) {
-   *     if (error) { cerr << error_message(error) << endl; exit(1); }
+   *     if (error) { cerr << error << endl; exit(1); }
    *     cout << std::string(doc["title"]) << endl;
    *   }
    *
@@ -1134,7 +1134,7 @@ public:
    *
    *   document::parser parser;
    *   for (auto [doc, error] : parser.parse_many(buf, len)) {
-   *     if (error) { cerr << error_message(error) << endl; exit(1); }
+   *     if (error) { cerr << error << endl; exit(1); }
    *     cout << std::string(doc["title"]) << endl;
    *   }
    *

include/simdjson/error.h

@@ -44,10 +44,26 @@ enum error_code {
  */
 inline const char *error_message(error_code error) noexcept;
 
+/**
+ * Write the error message to the output stream
+ */
+inline std::ostream& operator<<(std::ostream& out, error_code error) noexcept;
+
+/**
+ * Exception thrown when an exception-supporting simdjson method is called
+ */
 struct invalid_json : public std::exception {
-  invalid_json(error_code _error) noexcept : error{_error} { }
+  /**
-  const char *what() const noexcept { return error_message(error); }
+   * Create an exception from a simdjson error code.
-  error_code error;
+   * @param error The error code
+   */
+  invalid_json(error_code error) noexcept : _error{error} { }
+  /** The error message */
+  const char *what() const noexcept { return error_message(error()); }
+  error_code error() const noexcept { return _error; }
+private:
+  /** The error code that was used */
+  error_code _error;
 };
 
 /**

include/simdjson/inline/error.h

@@ -50,6 +50,10 @@ inline const std::string &error_message(int error) noexcept {
   return internal::error_codes[error].message;
 }
 
+inline std::ostream& operator<<(std::ostream& out, error_code error) noexcept {
+  return out << error_message(error);
+}
+
 } // namespace simdjson
 
 #endif // SIMDJSON_INLINE_ERROR_H

singleheader/amalgamation_demo.cpp

@@ -13,7 +13,7 @@ int main(int argc, char *argv[]) {
   if (error) {
     std::cout << "document::parse failed" << std::endl;
     std::cout << "error code: " << error << std::endl;
-    std::cout << error_message(error) << std::endl;
+    std::cout << error << std::endl;
   } else {
     std::cout << "document::parse valid" << std::endl;
   }

tests/basictests.cpp

@@ -254,7 +254,7 @@ static bool parse_json_message_issue467(char const* message, std::size_t len, si
     simdjson::padded_string str(message,len);
     for (auto [doc, error] : parser.parse_many(str, parser.capacity())) {
       if (error) {
-          std::cerr << "Failed with simdjson error= " << simdjson::error_message(error) << std::endl;
+          std::cerr << "Failed with simdjson error= " << error << std::endl;
           return false;
       }
       count++;
@@ -784,7 +784,7 @@ namespace dom_api {
     if (uint64_t(doc["a"]) != 1) { cerr << "Expected uint64_t(doc[\"a\"]) to be 1, was " << uint64_t(doc["a"]) << endl; return false; }
 
     auto [val, error] = doc["d"];
-    if (error != simdjson::NO_SUCH_FIELD) { cerr << "Expected NO_SUCH_FIELD error for uint64_t(doc[\"d\"]), got " << error_message(error) << endl; return false; }
+    if (error != simdjson::NO_SUCH_FIELD) { cerr << "Expected NO_SUCH_FIELD error for uint64_t(doc[\"d\"]), got " << error << endl; return false; }
     return true;
   }
 
@@ -802,7 +802,7 @@ namespace dom_api {
     if (uint64_t(obj["a"]) != 1) { cerr << "Expected uint64_t(obj[\"a\"]) to be 1, was " << uint64_t(obj["a"]) << endl; return false; }
 
     auto [val, error] = obj["d"];
-    if (error != simdjson::NO_SUCH_FIELD) { cerr << "Expected NO_SUCH_FIELD error for uint64_t(obj[\"d\"]), got " << error_message(error) << endl; return false; }
+    if (error != simdjson::NO_SUCH_FIELD) { cerr << "Expected NO_SUCH_FIELD error for uint64_t(obj[\"d\"]), got " << error << endl; return false; }
     return true;
   }
 

tests/parse_many_test.cpp

@@ -99,7 +99,7 @@ bool validate(const char *dirname) {
             } else if (starts_with("pass", name) and (has_extension(extension1, name) or has_extension(extension2, name)) and error) {
                 is_file_as_expected[i] = false;
                 printf("warning: file %s should pass but it fails. Error is: %s\n",
-                       name, simdjson::error_message(error).data());
+                       name, error_message(error));
                 printf("size of file in bytes: %zu \n", json.size());
                 everything_fine = false;
             } else if ( starts_with("fail", name) and (not starts_with("fail10.json", name)) and !error) {

tests/readme_examples.cpp

@@ -8,7 +8,7 @@ void document_parse_error_code() {
 
   string json("[ 1, 2, 3 ]");
   auto [doc, error] = document::parse(json);
-  if (error) { cerr << "Error: " << error_message(error) << endl; exit(1); }
+  if (error) { cerr << "Error: " << error << endl; exit(1); }
   if (!doc.print_json(cout)) { exit(1); }
   cout << endl;
 }
@@ -51,7 +51,7 @@ void parser_parse() {
   for (padded_string json : { string("[1, 2, 3]"), string("true"), string("[ true, false ]") }) {
     cout << "Parsing " << json.data() << " ..." << endl;
     auto [doc, error] = parser.parse(json);
-    if (error) { cerr << "Error: " << error_message(error) << endl; exit(1); }
+    if (error) { cerr << "Error: " << error << endl; exit(1); }
     if (!doc.print_json(cout)) { exit(1); }
     cout << endl;
   }
@@ -65,7 +65,7 @@ void parser_parse_many_error_code() {
   cout << "Parsing " << json.data() << " ..." << endl;
   document::parser parser;
   for (auto [doc, error] : parser.parse_many(json)) {
-    if (error) { cerr << "Error: " << error_message(error) << endl; exit(1); }
+    if (error) { cerr << "Error: " << error << endl; exit(1); }
     if (!doc.print_json(cout)) { exit(1); }
     cout << endl;
   }