Add parse error codes and API for converting error code to text.

Parse errors is represented as enum type `ParseErrorCode`.
Error texts are optional for user.
Added  `GetParseError_En()` in `error/en.h`, user can localize this file
into other files. User may dynamically change the locale in runtime.

example/condense/condense.cpp

@@ -7,6 +7,7 @@
 #include "rapidjson/writer.h"
 #include "rapidjson/filereadstream.h"
 #include "rapidjson/filewritestream.h"
+#include "rapidjson/error/en.h"
 
 using namespace rapidjson;
 
@@ -23,7 +24,7 @@ int main(int, char*[]) {
 
 	// JSON reader parse from the input stream and let writer generate the output.
 	if (!reader.Parse<0>(is, writer)) {
-		fprintf(stderr, "\nError(%u): %s\n", (unsigned)reader.GetErrorOffset(), reader.GetParseError());
+		fprintf(stderr, "\nError(%u): %s\n", (unsigned)reader.GetErrorOffset(), GetParseError_En(reader.GetParseErrorCode()));
 		return 1;
 	}
 

example/pretty/pretty.cpp

@@ -5,6 +5,7 @@
 #include "rapidjson/prettywriter.h"
 #include "rapidjson/filereadstream.h"
 #include "rapidjson/filewritestream.h"
+#include "rapidjson/error/en.h"
 
 using namespace rapidjson;
 
@@ -21,7 +22,7 @@ int main(int, char*[]) {
 
 	// JSON reader parse from the input stream and let writer generate the output.
 	if (!reader.Parse<kParseValidateEncodingFlag>(is, writer)) {
-		fprintf(stderr, "\nError(%u): %s\n", (unsigned)reader.GetErrorOffset(), reader.GetParseError());
+		fprintf(stderr, "\nError(%u): %s\n", (unsigned)reader.GetErrorOffset(), GetParseError_En(reader.GetParseErrorCode()));
 		return 1;
 	}
 

example/prettyauto/prettyauto.cpp

@@ -7,6 +7,7 @@
 #include "rapidjson/filereadstream.h"
 #include "rapidjson/filewritestream.h"
 #include "rapidjson/encodedstream.h"	// NEW
+#include "rapidjson/error/en.h"
 #ifdef _WIN32
 #include <fcntl.h>
 #include <io.h>
@@ -47,7 +48,7 @@ int main(int, char*[]) {
 	// JSON reader parse from the input stream and let writer generate the output.
 	//if (!reader.Parse<kParseValidateEncodingFlag>(is, writer)) {
 	if (!reader.Parse<kParseValidateEncodingFlag>(eis, writer)) {	// CHANGED
-		fprintf(stderr, "\nError(%u): %s\n", (unsigned)reader.GetErrorOffset(), reader.GetParseError());
+		fprintf(stderr, "\nError(%u): %s\n", (unsigned)reader.GetErrorOffset(), GetParseError_En(reader.GetParseErrorCode()));
 		return 1;
 	}
 

include/rapidjson/document.h

@@ -788,7 +788,7 @@ public:
 	/*! \param allocator		Optional allocator for allocating stack memory.
 		\param stackCapacity	Initial capacity of stack in bytes.
 	*/
-	GenericDocument(Allocator* allocator = 0, size_t stackCapacity = kDefaultStackCapacity) : stack_(allocator, stackCapacity), parseError_(0), errorOffset_(0) {}
+	GenericDocument(Allocator* allocator = 0, size_t stackCapacity = kDefaultStackCapacity) : stack_(allocator, stackCapacity), parseErrorCode_(kParseErrorNone), errorOffset_(0) {}
 
 	//! Parse JSON text from an input stream.
 	/*! \tparam parseFlags Combination of ParseFlag.
@@ -802,11 +802,11 @@ public:
 		if (reader.template Parse<parseFlags>(is, *this)) {
 			RAPIDJSON_ASSERT(stack_.GetSize() == sizeof(ValueType)); // Got one and only one root object
 			this->RawAssign(*stack_.template Pop<ValueType>(1));	// Add this-> to prevent issue 13.
-			parseError_ = 0;
+			parseErrorCode_ = kParseErrorNone;
 			errorOffset_ = 0;
 		}
 		else {
-			parseError_ = reader.GetParseError();
+			parseErrorCode_ = reader.GetParseErrorCode();
 			errorOffset_ = reader.GetErrorOffset();
 			ClearStack();
 		}
@@ -851,10 +851,10 @@ public:
 	}
 
 	//! Whether a parse error was occured in the last parsing.
-	bool HasParseError() const { return parseError_ != 0; }
+	bool HasParseError() const { return parseErrorCode_ != kParseErrorNone; }
 
 	//! Get the message of parsing error.
-	const char* GetParseError() const { return parseError_; }
+	ParseErrorCode GetParseError() const { return parseErrorCode_; }
 
 	//! Get the offset in character of the parsing error.
 	size_t GetErrorOffset() const { return errorOffset_; }
@@ -914,7 +914,7 @@ private:
 
 	static const size_t kDefaultStackCapacity = 1024;
 	internal::Stack<Allocator> stack_;
-	const char* parseError_;
+	ParseErrorCode parseErrorCode_;
 	size_t errorOffset_;
 };
 

include/rapidjson/error/en.h

+#ifndef RAPIDJSON_ERROR_EN_H__
+#define RAPIDJSON_ERROR_EN_H__
+
+#include "error.h"
+
+namespace rapidjson {
+
+inline const RAPIDJSON_ERROR_CHARTYPE* GetParseError_En(ParseErrorCode parseErrorCode) {
+	switch (parseErrorCode) {
+		case kParseErrorNone:							return RAPIDJSON_ERROR_STRING("No error.");
+
+		case kParseErrorDocumentEmpty:					return RAPIDJSON_ERROR_STRING("The document is empty.");
+		case kParseErrorDocumentRootNotObjectOrArray:	return RAPIDJSON_ERROR_STRING("The document root must be either object or array.");
+		case kParseErrorDocumentRootNotSingular:		return RAPIDJSON_ERROR_STRING("The document root must not follow by other values.");
+	
+		case kParseErrorValueInvalid:					return RAPIDJSON_ERROR_STRING("Invalid value.");
+	
+		case kParseErrorObjectMissName:					return RAPIDJSON_ERROR_STRING("Missing a name for object member.");
+		case kParseErrorObjectMissColon:				return RAPIDJSON_ERROR_STRING("Missing a colon after a name of object member.");
+		case kParseErrorObjectMissCommaOrCurlyBracket:	return RAPIDJSON_ERROR_STRING("Missing a comma or '}' after an object member.");
+	
+		case kParseErrorArrayMissCommaOrSquareBracket:	return RAPIDJSON_ERROR_STRING("Must be a comma or ']' after an array element.");
+
+		case kParseErrorStringUnicodeEscapeInvalidHex:	return RAPIDJSON_ERROR_STRING("Incorrect hex digit after \\u escape in string.");
+		case kParseErrorStringUnicodeSurrogateInvalid:	return RAPIDJSON_ERROR_STRING("The surrogate pair in string is invalid.");
+		case kParseErrorStringEscapeInvalid:			return RAPIDJSON_ERROR_STRING("Invalid escape character in string.");
+		case kParseErrorStringMissQuotationMark:		return RAPIDJSON_ERROR_STRING("Missing a closing quotation mark in string.");
+		case kParseErrorStringInvalidEncoding:			return RAPIDJSON_ERROR_STRING("Invalid encoidng in string.");
+
+		case kParesErrorNumberTooBig:					return RAPIDJSON_ERROR_STRING("Number too big to store in double.");
+		case kParseErrorNumberMissFraction:				return RAPIDJSON_ERROR_STRING("Miss fraction part in number.");
+		case kParseErrorNumberMissExponent:				return RAPIDJSON_ERROR_STRING("Miss exponent in number.");
+
+		default:
+			return RAPIDJSON_ERROR_STRING("Unknown error.");
+	}
+}
+
+} // namespace rapidjson
+
+#endif // RAPIDJSON_ERROR_EN_H__

include/rapidjson/error/error.h

+#ifndef RAPIDJSON_ERROR_ERROR_H__
+#define RAPIDJSON_ERROR_ERROR_H__
+
+// For example, on Windows, user can define this macro as TCHAR
+#ifndef RAPIDJSON_ERROR_CHARTYPE
+#define RAPIDJSON_ERROR_CHARTYPE char
+#endif
+
+// For example, on Windows, user can define this macro as _T(x)
+#ifndef RAPIDJSON_ERROR_STRING
+#define RAPIDJSON_ERROR_STRING(x) x
+#endif
+
+namespace rapidjson {
+
+// User can dynamically change locale in runtime, e.g.:
+//	GetParseErrorFunc GetParseError = GetParseError_En; // or whatever
+//	const RAPIDJSON_ERROR_CHARTYPE* s = GetParseError(document.GetParseErrorCode());
+
+typedef const RAPIDJSON_ERROR_CHARTYPE* (*GetParseErrorFunc)(ParseErrorCode);
+
+} // namespace rapidjson
+
+#endif // RAPIDJSON_ERROR_ERROR_H__
\ No newline at end of file

include/rapidjson/reader.h

@@ -21,19 +21,19 @@
 #endif
 
 #ifndef RAPIDJSON_PARSE_ERROR_NORETURN
-#define RAPIDJSON_PARSE_ERROR_NORETURN(msg, offset) \
+#define RAPIDJSON_PARSE_ERROR_NORETURN(parseErrorCode, offset) \
 	RAPIDJSON_MULTILINEMACRO_BEGIN \
 	if (!HasParseError()) {\
-		parseError_ = msg; \
+	parseErrorCode_ = parseErrorCode; \
 		errorOffset_ = offset; \
 	}\
 RAPIDJSON_MULTILINEMACRO_END
 #endif
 
 #ifndef RAPIDJSON_PARSE_ERROR
-#define RAPIDJSON_PARSE_ERROR(msg, offset) \
+#define RAPIDJSON_PARSE_ERROR(parseErrorCode, offset) \
 	RAPIDJSON_MULTILINEMACRO_BEGIN \
-	RAPIDJSON_PARSE_ERROR_NORETURN(msg, offset); \
+	RAPIDJSON_PARSE_ERROR_NORETURN(parseErrorCode, offset); \
 	return; \
 	RAPIDJSON_MULTILINEMACRO_END
 #endif
@@ -50,6 +50,33 @@ enum ParseFlag {
 	kParseValidateEncodingFlag = 2	//!< Validate encoding of JSON strings.
 };
 
+//! Error code of parsing.
+enum ParseErrorCode {
+	kParseErrorNone = 0,						//!< No error.
+	
+	kParseErrorDocumentEmpty,					//!< The document is empty.
+	kParseErrorDocumentRootNotObjectOrArray,	//!< The document root must be either object or array.
+	kParseErrorDocumentRootNotSingular,			//!< The document root must not follow by other values.
+	
+	kParseErrorValueInvalid,					//!< Invalid value.
+	
+	kParseErrorObjectMissName,					//!< Missing a name for object member.
+	kParseErrorObjectMissColon,					//!< Missing a colon after a name of object member.
+	kParseErrorObjectMissCommaOrCurlyBracket,	//!< Missing a comma or '}' after an object member.
+	
+	kParseErrorArrayMissCommaOrSquareBracket,	//!< Must be a comma or ']' after an array element.
+
+	kParseErrorStringUnicodeEscapeInvalidHex,	//!< Incorrect hex digit after \\u escape in string.
+	kParseErrorStringUnicodeSurrogateInvalid,	//!< The surrogate pair in string is invalid.
+	kParseErrorStringEscapeInvalid,				//!< Invalid escape character in string.
+	kParseErrorStringMissQuotationMark,			//!< Missing a closing quotation mark in string.
+	kParseErrorStringInvalidEncoding,			//!< Invalid encoidng in string.
+
+	kParesErrorNumberTooBig,					//!< Number too big to store in double.
+	kParseErrorNumberMissFraction,				//!< Miss fraction part in number.
+	kParseErrorNumberMissExponent				//!< Miss exponent in number.
+};
+
 ///////////////////////////////////////////////////////////////////////////////
 // Handler
 
@@ -218,7 +245,7 @@ public:
 	/*! \param allocator Optional allocator for allocating stack memory. (Only use for non-destructive parsing)
 		\param stackCapacity stack capacity in bytes for storing a single decoded string.  (Only use for non-destructive parsing)
 	*/
-	GenericReader(Allocator* allocator = 0, size_t stackCapacity = kDefaultStackCapacity) : stack_(allocator, stackCapacity), parseError_(0), errorOffset_(0) {}
+	GenericReader(Allocator* allocator = 0, size_t stackCapacity = kDefaultStackCapacity) : stack_(allocator, stackCapacity), parseErrorCode_(kParseErrorNone), errorOffset_(0) {}
 
 	//! Parse JSON text.
 	/*! \tparam parseFlags Combination of ParseFlag. 
@@ -230,31 +257,31 @@ public:
 	*/
 	template <unsigned parseFlags, typename InputStream, typename Handler>
 	bool Parse(InputStream& is, Handler& handler) {
-		parseError_ = 0;
+		parseErrorCode_ = kParseErrorNone;
 		errorOffset_ = 0;
 
 		SkipWhitespace(is);
 
 		if (is.Peek() == '\0')
-			RAPIDJSON_PARSE_ERROR_NORETURN("Text only contains white space(s)", is.Tell());
+			RAPIDJSON_PARSE_ERROR_NORETURN(kParseErrorDocumentEmpty, is.Tell());
 		else {
 			switch (is.Peek()) {
 				case '{': ParseObject<parseFlags>(is, handler); break;
 				case '[': ParseArray<parseFlags>(is, handler); break;
-				default: RAPIDJSON_PARSE_ERROR_NORETURN("Expect either an object or array at root", is.Tell());
+				default: RAPIDJSON_PARSE_ERROR_NORETURN(kParseErrorDocumentRootNotObjectOrArray, is.Tell());
 			}
 			SkipWhitespace(is);
 
 			if (is.Peek() != '\0')
-				RAPIDJSON_PARSE_ERROR_NORETURN("Nothing should follow the root object or array.", is.Tell());
+				RAPIDJSON_PARSE_ERROR_NORETURN(kParseErrorDocumentRootNotSingular, is.Tell());
 		}
 
 		stack_.Clear();
 		return !HasParseError();
 	}
 
-	bool HasParseError() const { return parseError_ != 0; }
-	const char* GetParseError() const { return parseError_; }
+	bool HasParseError() const { return parseErrorCode_ != kParseErrorNone; }
+	ParseErrorCode GetParseErrorCode() const { return parseErrorCode_; }
 	size_t GetErrorOffset() const { return errorOffset_; }
 
 private:
@@ -274,7 +301,7 @@ private:
 
 		for (SizeType memberCount = 0;;) {
 			if (is.Peek() != '"')
-				RAPIDJSON_PARSE_ERROR("Name of an object member must be a string", is.Tell());
+				RAPIDJSON_PARSE_ERROR(kParseErrorObjectMissName, is.Tell());
 
 			ParseString<parseFlags>(is, handler);
 			if (HasParseError())
@@ -283,7 +310,7 @@ private:
 			SkipWhitespace(is);
 
 			if (is.Take() != ':')
-				RAPIDJSON_PARSE_ERROR("There must be a colon after the name of object member", is.Tell());
+				RAPIDJSON_PARSE_ERROR(kParseErrorObjectMissColon, is.Tell());
 
 			SkipWhitespace(is);
 
@@ -298,7 +325,7 @@ private:
 			switch(is.Take()) {
 				case ',': SkipWhitespace(is); break;
 				case '}': handler.EndObject(memberCount); return;
-				default:  RAPIDJSON_PARSE_ERROR("Must be a comma or '}' after an object member", is.Tell());
+				default:  RAPIDJSON_PARSE_ERROR(kParseErrorObjectMissCommaOrCurlyBracket, is.Tell());
 			}
 		}
 	}
@@ -328,7 +355,7 @@ private:
 			switch (is.Take()) {
 				case ',': SkipWhitespace(is); break;
 				case ']': handler.EndArray(elementCount); return;
-				default:  RAPIDJSON_PARSE_ERROR("Must be a comma or ']' after an array element.", is.Tell());
+				default:  RAPIDJSON_PARSE_ERROR(kParseErrorArrayMissCommaOrSquareBracket, is.Tell());
 			}
 		}
 	}
@@ -341,7 +368,7 @@ private:
 		if (is.Take() == 'u' && is.Take() == 'l' && is.Take() == 'l')
 			handler.Null();
 		else
-			RAPIDJSON_PARSE_ERROR("Invalid value", is.Tell() - 1);
+			RAPIDJSON_PARSE_ERROR(kParseErrorValueInvalid, is.Tell() - 1);
 	}
 
 	template<unsigned parseFlags, typename InputStream, typename Handler>
@@ -352,7 +379,7 @@ private:
 		if (is.Take() == 'r' && is.Take() == 'u' && is.Take() == 'e')
 			handler.Bool(true);
 		else
-			RAPIDJSON_PARSE_ERROR("Invalid value", is.Tell());
+			RAPIDJSON_PARSE_ERROR(kParseErrorValueInvalid, is.Tell());
 	}
 
 	template<unsigned parseFlags, typename InputStream, typename Handler>
@@ -363,7 +390,7 @@ private:
 		if (is.Take() == 'a' && is.Take() == 'l' && is.Take() == 's' && is.Take() == 'e')
 			handler.Bool(false);
 		else
-			RAPIDJSON_PARSE_ERROR("Invalid value", is.Tell() - 1);
+			RAPIDJSON_PARSE_ERROR(kParseErrorValueInvalid, is.Tell() - 1);
 	}
 
 	// Helper function to parse four hexidecimal digits in \uXXXX in ParseString().
@@ -382,7 +409,7 @@ private:
 			else if (c >= 'a' && c <= 'f')
 				codepoint -= 'a' - 10;
 			else {
-				RAPIDJSON_PARSE_ERROR_NORETURN("Incorrect hex digit after \\u escape", s.Tell() - 1);
+				RAPIDJSON_PARSE_ERROR_NORETURN(kParseErrorStringUnicodeEscapeInvalidHex, s.Tell() - 1);
 				return 0;
 			}
 		}
@@ -455,16 +482,16 @@ private:
 					if (codepoint >= 0xD800 && codepoint <= 0xDBFF) {
 						// Handle UTF-16 surrogate pair
 						if (is.Take() != '\\' || is.Take() != 'u')
-							RAPIDJSON_PARSE_ERROR("Missing the second \\u in surrogate pair", is.Tell() - 2);
+							RAPIDJSON_PARSE_ERROR(kParseErrorStringUnicodeSurrogateInvalid, is.Tell() - 2);
 						unsigned codepoint2 = ParseHex4(is);
 						if (codepoint2 < 0xDC00 || codepoint2 > 0xDFFF)
-							RAPIDJSON_PARSE_ERROR("The second \\u in surrogate pair is invalid", is.Tell() - 2);
+							RAPIDJSON_PARSE_ERROR(kParseErrorStringUnicodeSurrogateInvalid, is.Tell() - 2);
 						codepoint = (((codepoint - 0xD800) << 10) | (codepoint2 - 0xDC00)) + 0x10000;
 					}
 					TEncoding::Encode(os, codepoint);
 				}
 				else
-					RAPIDJSON_PARSE_ERROR("Unknown escape character", is.Tell() - 1);
+					RAPIDJSON_PARSE_ERROR(kParseErrorStringEscapeInvalid, is.Tell() - 1);
 			}
 			else if (c == '"') {	// Closing double quote
 				is.Take();
@@ -472,14 +499,14 @@ private:
 				return;
 			}
 			else if (c == '\0')
-				RAPIDJSON_PARSE_ERROR("lacks ending quotation before the end of string", is.Tell() - 1);
+				RAPIDJSON_PARSE_ERROR(kParseErrorStringMissQuotationMark, is.Tell() - 1);
 			else if ((unsigned)c < 0x20) // RFC 4627: unescaped = %x20-21 / %x23-5B / %x5D-10FFFF
-				RAPIDJSON_PARSE_ERROR("Incorrect unescaped character in string", is.Tell() - 1);
+				RAPIDJSON_PARSE_ERROR(kParseErrorStringEscapeInvalid, is.Tell() - 1);
 			else {
 				if (parseFlags & kParseValidateEncodingFlag ? 
 					!Transcoder<SEncoding, TEncoding>::Validate(is, os) : 
 					!Transcoder<SEncoding, TEncoding>::Transcode(is, os))
-					RAPIDJSON_PARSE_ERROR("Invalid encoding", is.Tell());
+					RAPIDJSON_PARSE_ERROR(kParseErrorStringInvalidEncoding, is.Tell());
 			}
 		}
 	}
@@ -526,7 +553,7 @@ private:
 				}
 		}
 		else
-			RAPIDJSON_PARSE_ERROR("Expect a value here.", is.Tell());
+			RAPIDJSON_PARSE_ERROR(kParseErrorValueInvalid, is.Tell());
 
 		// Parse 64bit int
 		uint64_t i64 = 0;
@@ -559,7 +586,7 @@ private:
 			d = (double)i64;
 			while (s.Peek() >= '0' && s.Peek() <= '9') {
 				if (d >= 1E307)
-					RAPIDJSON_PARSE_ERROR("Number too big to store in double", is.Tell());
+					RAPIDJSON_PARSE_ERROR(kParesErrorNumberTooBig, is.Tell());
 				d = d * 10 + (s.Take() - '0');
 			}
 		}
@@ -578,7 +605,7 @@ private:
 				--expFrac;
 			}
 			else
-				RAPIDJSON_PARSE_ERROR("At least one digit in fraction part", is.Tell());
+				RAPIDJSON_PARSE_ERROR(kParseErrorNumberMissFraction, is.Tell());
 
 			while (s.Peek() >= '0' && s.Peek() <= '9') {
 				if (expFrac > -16) {
@@ -611,11 +638,11 @@ private:
 				while (s.Peek() >= '0' && s.Peek() <= '9') {
 					exp = exp * 10 + (s.Take() - '0');
 					if (exp > 308)
-						RAPIDJSON_PARSE_ERROR("Number too big to store in double", is.Tell());
+						RAPIDJSON_PARSE_ERROR(kParesErrorNumberTooBig, is.Tell());
 				}
 			}
 			else
-				RAPIDJSON_PARSE_ERROR("At least one digit in exponent", s.Tell());
+				RAPIDJSON_PARSE_ERROR(kParseErrorNumberMissExponent, s.Tell());
 
 			if (expMinus)
 				exp = -exp;
@@ -660,7 +687,7 @@ private:
 
 	static const size_t kDefaultStackCapacity = 256;	//!< Default stack capacity in bytes for storing a single decoded string. 
 	internal::Stack<Allocator> stack_;	//!< A stack for storing decoded string temporarily during non-destructive parsing.
-	const char* parseError_;
+	ParseErrorCode parseErrorCode_;
 	size_t errorOffset_;
 }; // class GenericReader