From: Mikko Rasa <tdb@tdb.fi>
Date: Sat, 28 May 2011 09:04:02 +0000 (+0300)
Subject: Exception improvements for lexical_cast
X-Git-Url: http://git.tdb.fi/?p=libs%2Fcore.git;a=commitdiff_plain;h=4a38eb20402936497cbb75527dd7a7b321f51415

Exception improvements for lexical_cast
---

diff --git a/source/strings/lexicalcast.cpp b/source/strings/lexicalcast.cpp
index 5903bb1..a91c18c 100644
--- a/source/strings/lexicalcast.cpp
+++ b/source/strings/lexicalcast.cpp
@@ -7,6 +7,7 @@ Distributed under the LGPL
 
 #include <cmath>
 #include <limits>
+#include "format.h"
 #include "lexicalcast.h"
 
 using namespace std;
@@ -130,7 +131,7 @@ template<typename T>
 T str_to_int(const std::string &s, const Fmt &f)
 {
 	if(s.empty())
-		throw LexicalError("Empty input in integer conversion");
+		throw lexical_error("conversion of '' to integer");
 
 	std::string::const_iterator i = s.begin();
 
@@ -139,7 +140,7 @@ T str_to_int(const std::string &s, const Fmt &f)
 	if(*i=='-')
 	{
 		if(!IsSigned<T>::result)
-			throw LexicalError("Negative sign in unsigned integer conversion");
+			throw lexical_error(format("conversion of '%s' to unsigned integer", s));
 		neg = true;
 		++i;
 	}
@@ -148,7 +149,7 @@ T str_to_int(const std::string &s, const Fmt &f)
 
 	// Must have some digits to convert
 	if(i==s.end())
-		throw LexicalError("Missing digits in integer conversion");
+		throw lexical_error(format("conversion of '%s' to integer", s));
 
 	T base = f.get_base();
 	if(!base && i!=s.end())
@@ -185,10 +186,10 @@ T str_to_int(const std::string &s, const Fmt &f)
 		else if(*i>='a' && *i<='f')
 			digit = *i-'a'+10;
 		if(digit>=base)
-			throw LexicalError("Invalid digit in integer conversion");
+			throw lexical_error(format("conversion of '%s' to integer (base-%d)", s, base));
 		T next = result*base+digit;
 		if(next/base!=result)
-			throw LexicalError("Overflow in integer conversion");
+			throw lexical_error(format("conversion of '%s' to %d-bit integer", s, sizeof(T)*8));
 		result = next;
 	}
 
@@ -212,14 +213,14 @@ string bool_to_str(bool b, const Fmt &f)
 bool str_to_bool(const string &s)
 {
 	if(s.empty())
-		throw LexicalError("Empty input in boolean conversion");
+		throw lexical_error("conversion of '' to boolean");
 
 	if(s=="1" || s=="true" || s=="yes" || s=="on")
 		return true;
 	else if(s=="0" || s=="false" || s=="no" || s=="off")
 		return false;
 
-	throw LexicalError("Invalid input in boolean conversion");
+	throw lexical_error(format("conversion of '%s' to boolean", s));
 }
 
 
@@ -229,7 +230,7 @@ template<typename T>
 string flt_to_str(T v, const Fmt &f)
 {
 	if(f.get_type()==Fmt::CHAR)
-		throw LexicalError("Character format in floating-point conversion");
+		throw format_mismatch("floating-point conversion with character format");
 
 	Fmt::FloatMode mode = f.get_floatmode();
 	long double w = abs(v);
@@ -395,7 +396,7 @@ template<typename T>
 T str_to_flt(const string &s, const Fmt &)
 {
 	if(s.empty())
-		throw LexicalError("Empty input in floating-point conversion");
+		throw lexical_error("conversion of '' to floating-point");
 
 	std::string::const_iterator i = s.begin();
 
@@ -411,7 +412,7 @@ T str_to_flt(const string &s, const Fmt &)
 
 	// Must have some digits to convert
 	if(i==s.end())
-		throw LexicalError("Missing digits in floating-point conversion");
+		throw lexical_error(format("conversion of '%s' to floating-point", s));
 
 	long double v = 0;
 	int exp = 0;
@@ -423,7 +424,7 @@ T str_to_flt(const string &s, const Fmt &)
 		if(*i=='.')
 		{
 			if(point_seen)
-				throw LexicalError("Extra point in floating-point conversion");
+				throw lexical_error(format("conversion of '%s' to floating-point", s));
 			point_seen = true;
 		}
 		else if(*i>='0' && *i<='9')
@@ -442,7 +443,7 @@ T str_to_flt(const string &s, const Fmt &)
 			break;
 		}
 		else
-			throw LexicalError("Invalid digit in floating-point conversion");
+			throw lexical_error(format("conversion of '%s' to floating-point", s));
 	}
 
 	// Scale and negate the result as needed
@@ -469,7 +470,7 @@ T str_to_flt(const string &s, const Fmt &)
 string str_to_str(const string &s, const Fmt &f)
 {
 	if(f.get_type()==Fmt::NUM)
-		throw LexicalError("Numeric format in string conversion");
+		throw format_mismatch("string conversion with numeric format");
 	return s;
 }
 
@@ -566,9 +567,9 @@ void operator>>(const LexicalConverter &c, char &v)
 	{
 		const std::string &s = c.get();
 		if(s.empty())
-			throw LexicalError("Empty input in character conversion");
+			throw lexical_error("conversion of '' to character");
 		if(s.size()>1)
-			throw LexicalError("Extra input in character conversion");
+			throw lexical_error(format("conversion of '%s' to character", s));
 		v = s[0];
 	}
 }
diff --git a/source/strings/lexicalcast.h b/source/strings/lexicalcast.h
index 3bfc342..b41654d 100644
--- a/source/strings/lexicalcast.h
+++ b/source/strings/lexicalcast.h
@@ -10,7 +10,7 @@ Distributed under the LGPL
 
 #include <sstream>
 #include <string>
-#include <msp/core/except.h>
+#include <stdexcept>
 #include "fmt.h"
 
 namespace Msp {
@@ -18,10 +18,19 @@ namespace Msp {
 /**
 Thrown for errors in lexical conversions
 */
-class LexicalError: public Exception
+class lexical_error: public std::runtime_error
 {
 public:
-	LexicalError(const std::string &w_): Exception(w_) { }
+	lexical_error(const std::string &w): runtime_error(w) { }
+	virtual ~lexical_error() throw() { }
+};
+
+
+class format_mismatch: public lexical_error
+{
+public:
+	format_mismatch(const std::string &w): lexical_error(w) { }
+	virtual ~format_mismatch() throw() { }
 };
 
 
@@ -101,7 +110,7 @@ void operator>>(const LexicalConverter &c, T &v)
 	ss.setf(std::ios_base::fmtflags(0), std::ios_base::skipws);
 	ss>>v;
 	if(ss.fail() || !ss.eof())
-		throw LexicalError("Conversion failure");
+		throw lexical_error("conversion failure");
 }
 
 // The main interface to the lexical conversion machinery