Source/JavaScriptCore/runtime/NumberPrototype.cpp - platform/external/webkit - Git at Google

 /*
  *  Copyright (C) 1999-2000,2003 Harri Porten (porten@kde.org)
  *  Copyright (C) 2007, 2008 Apple Inc. All rights reserved.
  *
  *  This library is free software; you can redistribute it and/or
  *  modify it under the terms of the GNU Lesser General Public
  *  License as published by the Free Software Foundation; either
  *  version 2 of the License, or (at your option) any later version.
  *
  *  This library is distributed in the hope that it will be useful,
  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  *  Lesser General Public License for more details.
  *
  *  You should have received a copy of the GNU Lesser General Public
  *  License along with this library; if not, write to the Free Software
  *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301
  *  USA
  *
  */

 #include "config.h"
 #include "NumberPrototype.h"

 #include "Error.h"
 #include "JSFunction.h"
 #include "JSString.h"
 #include "Operations.h"
 #include "dtoa.h"
 #include <wtf/Assertions.h>
 #include <wtf/DecimalNumber.h>
 #include <wtf/MathExtras.h>
 #include <wtf/Vector.h>

 namespace JSC {

 ASSERT_CLASS_FITS_IN_CELL(NumberPrototype);

 static EncodedJSValue JSC_HOST_CALL numberProtoFuncToString(ExecState*);
 static EncodedJSValue JSC_HOST_CALL numberProtoFuncToLocaleString(ExecState*);
 static EncodedJSValue JSC_HOST_CALL numberProtoFuncValueOf(ExecState*);
 static EncodedJSValue JSC_HOST_CALL numberProtoFuncToFixed(ExecState*);
 static EncodedJSValue JSC_HOST_CALL numberProtoFuncToExponential(ExecState*);
 static EncodedJSValue JSC_HOST_CALL numberProtoFuncToPrecision(ExecState*);

 // ECMA 15.7.4

 NumberPrototype::NumberPrototype(ExecState* exec, JSGlobalObject* globalObject, Structure* structure, Structure* functionStructure)
     : NumberObject(exec->globalData(), structure)
 {
     setInternalValue(exec->globalData(), jsNumber(0));

     // The constructor will be added later, after NumberConstructor has been constructed

     putDirectFunctionWithoutTransition(exec, new (exec) JSFunction(exec, globalObject, functionStructure, 1, exec->propertyNames().toString, numberProtoFuncToString), DontEnum);
     putDirectFunctionWithoutTransition(exec, new (exec) JSFunction(exec, globalObject, functionStructure, 0, exec->propertyNames().toLocaleString, numberProtoFuncToLocaleString), DontEnum);
     putDirectFunctionWithoutTransition(exec, new (exec) JSFunction(exec, globalObject, functionStructure, 0, exec->propertyNames().valueOf, numberProtoFuncValueOf), DontEnum);
     putDirectFunctionWithoutTransition(exec, new (exec) JSFunction(exec, globalObject, functionStructure, 1, exec->propertyNames().toFixed, numberProtoFuncToFixed), DontEnum);
     putDirectFunctionWithoutTransition(exec, new (exec) JSFunction(exec, globalObject, functionStructure, 1, exec->propertyNames().toExponential, numberProtoFuncToExponential), DontEnum);
     putDirectFunctionWithoutTransition(exec, new (exec) JSFunction(exec, globalObject, functionStructure, 1, exec->propertyNames().toPrecision, numberProtoFuncToPrecision), DontEnum);
 }

 // ------------------------------ Functions ---------------------------

 // ECMA 15.7.4.2 - 15.7.4.7

 static ALWAYS_INLINE bool toThisNumber(JSValue thisValue, double &x)
 {
     JSValue v = thisValue.getJSNumber();
     if (UNLIKELY(!v))
         return false;
     x = v.uncheckedGetNumber();
     return true;
 }

 static ALWAYS_INLINE bool getIntegerArgumentInRange(ExecState* exec, int low, int high, int& result, bool& isUndefined)
 {
     result = 0;
     isUndefined = false;

     JSValue argument0 = exec->argument(0);
     if (argument0.isUndefined()) {
         isUndefined = true;
         return true;
     }

     double asDouble = argument0.toInteger(exec);
     if (asDouble < low || asDouble > high)
         return false;

     result = static_cast<int>(asDouble);
     return true;
 }

 // toExponential converts a number to a string, always formatting as an expoential.
 // This method takes an optional argument specifying a number of *decimal places*
 // to round the significand to (or, put another way, this method optionally rounds
 // to argument-plus-one significant figures).
 EncodedJSValue JSC_HOST_CALL numberProtoFuncToExponential(ExecState* exec)
 {
     // Get x (the double value of this, which should be a Number).
     double x;
     if (!toThisNumber(exec->hostThisValue(), x))
         return throwVMTypeError(exec);

     // Get the argument.
     int decimalPlacesInExponent;
     bool isUndefined;
     if (!getIntegerArgumentInRange(exec, 0, 20, decimalPlacesInExponent, isUndefined))
         return throwVMError(exec, createRangeError(exec, "toExponential() argument must be between 0 and 20"));

     // Handle NaN and Infinity.
     if (isnan(x) || isinf(x))
         return JSValue::encode(jsString(exec, UString::number(x)));

     // Round if the argument is not undefined, always format as exponential.
     NumberToStringBuffer buffer;
     unsigned length = isUndefined
         ? DecimalNumber(x).toStringExponential(buffer, WTF::NumberToStringBufferLength)
         : DecimalNumber(x, RoundingSignificantFigures, decimalPlacesInExponent + 1).toStringExponential(buffer, WTF::NumberToStringBufferLength);

     return JSValue::encode(jsString(exec, UString(buffer, length)));
 }

 // toFixed converts a number to a string, always formatting as an a decimal fraction.
 // This method takes an argument specifying a number of decimal places to round the
 // significand to. However when converting large values (1e+21 and above) this
 // method will instead fallback to calling ToString.
 EncodedJSValue JSC_HOST_CALL numberProtoFuncToFixed(ExecState* exec)
 {
     // Get x (the double value of this, which should be a Number).
     JSValue thisValue = exec->hostThisValue();
     JSValue v = thisValue.getJSNumber();
     if (!v)
         return throwVMTypeError(exec);
     double x = v.uncheckedGetNumber();

     // Get the argument.
     int decimalPlaces;
     bool isUndefined; // This is ignored; undefined treated as 0.
     if (!getIntegerArgumentInRange(exec, 0, 20, decimalPlaces, isUndefined))
         return throwVMError(exec, createRangeError(exec, "toFixed() argument must be between 0 and 20"));

     // 15.7.4.5.7 states "If x >= 10^21, then let m = ToString(x)"
     // This also covers Ininity, and structure the check so that NaN
     // values are also handled by numberToString
     if (!(fabs(x) < 1e+21))
         return JSValue::encode(jsString(exec, UString::number(x)));

     // The check above will return false for NaN or Infinity, these will be
     // handled by numberToString.
     ASSERT(!isnan(x) && !isinf(x));

     // Convert to decimal with rounding, and format as decimal.
     NumberToStringBuffer buffer;
     unsigned length = DecimalNumber(x, RoundingDecimalPlaces, decimalPlaces).toStringDecimal(buffer, WTF::NumberToStringBufferLength);
     return JSValue::encode(jsString(exec, UString(buffer, length)));
 }

 // toPrecision converts a number to a string, takeing an argument specifying a
 // number of significant figures to round the significand to. For positive
 // exponent, all values that can be represented using a decimal fraction will
 // be, e.g. when rounding to 3 s.f. any value up to 999 will be formated as a
 // decimal, whilst 1000 is converted to the exponential representation 1.00e+3.
 // For negative exponents values >= 1e-6 are formated as decimal fractions,
 // with smaller values converted to exponential representation.
 EncodedJSValue JSC_HOST_CALL numberProtoFuncToPrecision(ExecState* exec)
 {
     // Get x (the double value of this, which should be a Number).
     JSValue thisValue = exec->hostThisValue();
     JSValue v = thisValue.getJSNumber();
     if (!v)
         return throwVMTypeError(exec);
     double x = v.uncheckedGetNumber();

     // Get the argument.
     int significantFigures;
     bool isUndefined;
     if (!getIntegerArgumentInRange(exec, 1, 21, significantFigures, isUndefined))
         return throwVMError(exec, createRangeError(exec, "toPrecision() argument must be between 1 and 21"));

     // To precision called with no argument is treated as ToString.
     if (isUndefined)
         return JSValue::encode(jsString(exec, UString::number(x)));

     // Handle NaN and Infinity.
     if (isnan(x) || isinf(x))
         return JSValue::encode(jsString(exec, UString::number(x)));

     // Convert to decimal with rounding.
     DecimalNumber number(x, RoundingSignificantFigures, significantFigures);
     // If number is in the range 1e-6 <= x < pow(10, significantFigures) then format
     // as decimal. Otherwise, format the number as an exponential.  Decimal format
     // demands a minimum of (exponent + 1) digits to represent a number, for example
     // 1234 (1.234e+3) requires 4 digits. (See ECMA-262 15.7.4.7.10.c)
     NumberToStringBuffer buffer;
     unsigned length = number.exponent() >= -6 && number.exponent() < significantFigures
         ? number.toStringDecimal(buffer, WTF::NumberToStringBufferLength)
         : number.toStringExponential(buffer, WTF::NumberToStringBufferLength);
     return JSValue::encode(jsString(exec, UString(buffer, length)));
 }

 EncodedJSValue JSC_HOST_CALL numberProtoFuncToString(ExecState* exec)
 {
     JSValue thisValue = exec->hostThisValue();
     JSValue v = thisValue.getJSNumber();
     if (!v)
         return throwVMTypeError(exec);

     JSValue radixValue = exec->argument(0);
     int radix;
     if (radixValue.isInt32())
         radix = radixValue.asInt32();
     else if (radixValue.isUndefined())
         radix = 10;
     else
         radix = static_cast<int>(radixValue.toInteger(exec)); // nan -> 0

     if (radix == 10)
         return JSValue::encode(jsString(exec, v.toString(exec)));

     static const char* const digits = "0123456789abcdefghijklmnopqrstuvwxyz";

     // Fast path for number to character conversion.
     if (radix == 36) {
         if (v.isInt32()) {
             int x = v.asInt32();
             if (static_cast<unsigned>(x) < 36) { // Exclude negatives
                 JSGlobalData* globalData = &exec->globalData();
                 return JSValue::encode(globalData->smallStrings.singleCharacterString(globalData, digits[x]));
             }
         }
     }

     if (radix < 2 || radix > 36)
         return throwVMError(exec, createRangeError(exec, "toString() radix argument must be between 2 and 36"));

     // INT_MAX results in 1024 characters left of the dot with radix 2
     // give the same space on the right side. safety checks are in place
     // unless someone finds a precise rule.
     char s[2048 + 3];
     const char* lastCharInString = s + sizeof(s) - 1;
     double x = v.uncheckedGetNumber();
     if (isnan(x) || isinf(x))
         return JSValue::encode(jsString(exec, UString::number(x)));

     bool isNegative = x < 0.0;
     if (isNegative)
         x = -x;

     double integerPart = floor(x);
     char* decimalPoint = s + sizeof(s) / 2;

     // convert integer portion
     char* p = decimalPoint;
     double d = integerPart;
     do {
         int remainderDigit = static_cast<int>(fmod(d, radix));
         *--p = digits[remainderDigit];
         d /= radix;
     } while ((d <= -1.0 || d >= 1.0) && s < p);

     if (isNegative)
         *--p = '-';
     char* startOfResultString = p;
     ASSERT(s <= startOfResultString);

     d = x - integerPart;
     p = decimalPoint;
     const double epsilon = 0.001; // TODO: guessed. base on radix ?
     bool hasFractionalPart = (d < -epsilon || d > epsilon);
     if (hasFractionalPart) {
         *p++ = '.';
         do {
             d *= radix;
             const int digit = static_cast<int>(d);
             *p++ = digits[digit];
             d -= digit;
         } while ((d < -epsilon || d > epsilon) && p < lastCharInString);
     }
     *p = '\0';
     ASSERT(p < s + sizeof(s));

     return JSValue::encode(jsString(exec, startOfResultString));
 }

 EncodedJSValue JSC_HOST_CALL numberProtoFuncToLocaleString(ExecState* exec)
 {
     JSValue thisValue = exec->hostThisValue();
     // FIXME: Not implemented yet.

     JSValue v = thisValue.getJSNumber();
     if (!v)
         return throwVMTypeError(exec);

     return JSValue::encode(jsString(exec, v.toString(exec)));
 }

 EncodedJSValue JSC_HOST_CALL numberProtoFuncValueOf(ExecState* exec)
 {
     JSValue thisValue = exec->hostThisValue();
     JSValue v = thisValue.getJSNumber();
     if (!v)
         return throwVMTypeError(exec);

     return JSValue::encode(v);
 }

 } // namespace JSC
	/*
	* Copyright (C) 1999-2000,2003 Harri Porten (porten@kde.org)
	* Copyright (C) 2007, 2008 Apple Inc. All rights reserved.
	*
	* This library is free software; you can redistribute it and/or
	* modify it under the terms of the GNU Lesser General Public
	* License as published by the Free Software Foundation; either
	* version 2 of the License, or (at your option) any later version.
	*
	* This library is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	* Lesser General Public License for more details.
	*
	* You should have received a copy of the GNU Lesser General Public
	* License along with this library; if not, write to the Free Software
	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301
	* USA
	*
	*/

	#include "config.h"
	#include "NumberPrototype.h"

	#include "Error.h"
	#include "JSFunction.h"
	#include "JSString.h"
	#include "Operations.h"
	#include "dtoa.h"
	#include <wtf/Assertions.h>
	#include <wtf/DecimalNumber.h>
	#include <wtf/MathExtras.h>
	#include <wtf/Vector.h>

	namespace JSC {

	ASSERT_CLASS_FITS_IN_CELL(NumberPrototype);

	static EncodedJSValue JSC_HOST_CALL numberProtoFuncToString(ExecState*);
	static EncodedJSValue JSC_HOST_CALL numberProtoFuncToLocaleString(ExecState*);
	static EncodedJSValue JSC_HOST_CALL numberProtoFuncValueOf(ExecState*);
	static EncodedJSValue JSC_HOST_CALL numberProtoFuncToFixed(ExecState*);
	static EncodedJSValue JSC_HOST_CALL numberProtoFuncToExponential(ExecState*);
	static EncodedJSValue JSC_HOST_CALL numberProtoFuncToPrecision(ExecState*);

	// ECMA 15.7.4

	NumberPrototype::NumberPrototype(ExecState* exec, JSGlobalObject* globalObject, Structure* structure, Structure* functionStructure)
	: NumberObject(exec->globalData(), structure)
	{
	setInternalValue(exec->globalData(), jsNumber(0));

	// The constructor will be added later, after NumberConstructor has been constructed

	putDirectFunctionWithoutTransition(exec, new (exec) JSFunction(exec, globalObject, functionStructure, 1, exec->propertyNames().toString, numberProtoFuncToString), DontEnum);
	putDirectFunctionWithoutTransition(exec, new (exec) JSFunction(exec, globalObject, functionStructure, 0, exec->propertyNames().toLocaleString, numberProtoFuncToLocaleString), DontEnum);
	putDirectFunctionWithoutTransition(exec, new (exec) JSFunction(exec, globalObject, functionStructure, 0, exec->propertyNames().valueOf, numberProtoFuncValueOf), DontEnum);
	putDirectFunctionWithoutTransition(exec, new (exec) JSFunction(exec, globalObject, functionStructure, 1, exec->propertyNames().toFixed, numberProtoFuncToFixed), DontEnum);
	putDirectFunctionWithoutTransition(exec, new (exec) JSFunction(exec, globalObject, functionStructure, 1, exec->propertyNames().toExponential, numberProtoFuncToExponential), DontEnum);
	putDirectFunctionWithoutTransition(exec, new (exec) JSFunction(exec, globalObject, functionStructure, 1, exec->propertyNames().toPrecision, numberProtoFuncToPrecision), DontEnum);
	}

	// ------------------------------ Functions ---------------------------

	// ECMA 15.7.4.2 - 15.7.4.7

	static ALWAYS_INLINE bool toThisNumber(JSValue thisValue, double &x)
	{
	JSValue v = thisValue.getJSNumber();
	if (UNLIKELY(!v))
	return false;
	x = v.uncheckedGetNumber();
	return true;
	}

	static ALWAYS_INLINE bool getIntegerArgumentInRange(ExecState* exec, int low, int high, int& result, bool& isUndefined)
	{
	result = 0;
	isUndefined = false;

	JSValue argument0 = exec->argument(0);
	if (argument0.isUndefined()) {
	isUndefined = true;
	return true;
	}

	double asDouble = argument0.toInteger(exec);
	if (asDouble < low \|\| asDouble > high)
	return false;

	result = static_cast<int>(asDouble);
	return true;
	}

	// toExponential converts a number to a string, always formatting as an expoential.
	// This method takes an optional argument specifying a number of decimal places
	// to round the significand to (or, put another way, this method optionally rounds
	// to argument-plus-one significant figures).
	EncodedJSValue JSC_HOST_CALL numberProtoFuncToExponential(ExecState* exec)
	{
	// Get x (the double value of this, which should be a Number).
	double x;
	if (!toThisNumber(exec->hostThisValue(), x))
	return throwVMTypeError(exec);

	// Get the argument.
	int decimalPlacesInExponent;
	bool isUndefined;
	if (!getIntegerArgumentInRange(exec, 0, 20, decimalPlacesInExponent, isUndefined))
	return throwVMError(exec, createRangeError(exec, "toExponential() argument must be between 0 and 20"));

	// Handle NaN and Infinity.
	if (isnan(x) \|\| isinf(x))
	return JSValue::encode(jsString(exec, UString::number(x)));

	// Round if the argument is not undefined, always format as exponential.
	NumberToStringBuffer buffer;
	unsigned length = isUndefined
	? DecimalNumber(x).toStringExponential(buffer, WTF::NumberToStringBufferLength)
	: DecimalNumber(x, RoundingSignificantFigures, decimalPlacesInExponent + 1).toStringExponential(buffer, WTF::NumberToStringBufferLength);

	return JSValue::encode(jsString(exec, UString(buffer, length)));
	}

	// toFixed converts a number to a string, always formatting as an a decimal fraction.
	// This method takes an argument specifying a number of decimal places to round the
	// significand to. However when converting large values (1e+21 and above) this
	// method will instead fallback to calling ToString.
	EncodedJSValue JSC_HOST_CALL numberProtoFuncToFixed(ExecState* exec)
	{
	// Get x (the double value of this, which should be a Number).
	JSValue thisValue = exec->hostThisValue();
	JSValue v = thisValue.getJSNumber();
	if (!v)
	return throwVMTypeError(exec);
	double x = v.uncheckedGetNumber();

	// Get the argument.
	int decimalPlaces;
	bool isUndefined; // This is ignored; undefined treated as 0.
	if (!getIntegerArgumentInRange(exec, 0, 20, decimalPlaces, isUndefined))
	return throwVMError(exec, createRangeError(exec, "toFixed() argument must be between 0 and 20"));

	// 15.7.4.5.7 states "If x >= 10^21, then let m = ToString(x)"
	// This also covers Ininity, and structure the check so that NaN
	// values are also handled by numberToString
	if (!(fabs(x) < 1e+21))
	return JSValue::encode(jsString(exec, UString::number(x)));

	// The check above will return false for NaN or Infinity, these will be
	// handled by numberToString.
	ASSERT(!isnan(x) && !isinf(x));

	// Convert to decimal with rounding, and format as decimal.
	NumberToStringBuffer buffer;
	unsigned length = DecimalNumber(x, RoundingDecimalPlaces, decimalPlaces).toStringDecimal(buffer, WTF::NumberToStringBufferLength);
	return JSValue::encode(jsString(exec, UString(buffer, length)));
	}

	// toPrecision converts a number to a string, takeing an argument specifying a
	// number of significant figures to round the significand to. For positive
	// exponent, all values that can be represented using a decimal fraction will
	// be, e.g. when rounding to 3 s.f. any value up to 999 will be formated as a
	// decimal, whilst 1000 is converted to the exponential representation 1.00e+3.
	// For negative exponents values >= 1e-6 are formated as decimal fractions,
	// with smaller values converted to exponential representation.
	EncodedJSValue JSC_HOST_CALL numberProtoFuncToPrecision(ExecState* exec)
	{
	// Get x (the double value of this, which should be a Number).
	JSValue thisValue = exec->hostThisValue();
	JSValue v = thisValue.getJSNumber();
	if (!v)
	return throwVMTypeError(exec);
	double x = v.uncheckedGetNumber();

	// Get the argument.
	int significantFigures;
	bool isUndefined;
	if (!getIntegerArgumentInRange(exec, 1, 21, significantFigures, isUndefined))
	return throwVMError(exec, createRangeError(exec, "toPrecision() argument must be between 1 and 21"));

	// To precision called with no argument is treated as ToString.
	if (isUndefined)
	return JSValue::encode(jsString(exec, UString::number(x)));

	// Handle NaN and Infinity.
	if (isnan(x) \|\| isinf(x))
	return JSValue::encode(jsString(exec, UString::number(x)));

	// Convert to decimal with rounding.
	DecimalNumber number(x, RoundingSignificantFigures, significantFigures);
	// If number is in the range 1e-6 <= x < pow(10, significantFigures) then format
	// as decimal. Otherwise, format the number as an exponential. Decimal format
	// demands a minimum of (exponent + 1) digits to represent a number, for example
	// 1234 (1.234e+3) requires 4 digits. (See ECMA-262 15.7.4.7.10.c)
	NumberToStringBuffer buffer;
	unsigned length = number.exponent() >= -6 && number.exponent() < significantFigures
	? number.toStringDecimal(buffer, WTF::NumberToStringBufferLength)
	: number.toStringExponential(buffer, WTF::NumberToStringBufferLength);
	return JSValue::encode(jsString(exec, UString(buffer, length)));
	}

	EncodedJSValue JSC_HOST_CALL numberProtoFuncToString(ExecState* exec)
	{
	JSValue thisValue = exec->hostThisValue();
	JSValue v = thisValue.getJSNumber();
	if (!v)
	return throwVMTypeError(exec);

	JSValue radixValue = exec->argument(0);
	int radix;
	if (radixValue.isInt32())
	radix = radixValue.asInt32();
	else if (radixValue.isUndefined())
	radix = 10;
	else
	radix = static_cast<int>(radixValue.toInteger(exec)); // nan -> 0

	if (radix == 10)
	return JSValue::encode(jsString(exec, v.toString(exec)));

	static const char* const digits = "0123456789abcdefghijklmnopqrstuvwxyz";

	// Fast path for number to character conversion.
	if (radix == 36) {
	if (v.isInt32()) {
	int x = v.asInt32();
	if (static_cast<unsigned>(x) < 36) { // Exclude negatives
	JSGlobalData* globalData = &exec->globalData();
	return JSValue::encode(globalData->smallStrings.singleCharacterString(globalData, digits[x]));
	}
	}
	}

	if (radix < 2 \|\| radix > 36)
	return throwVMError(exec, createRangeError(exec, "toString() radix argument must be between 2 and 36"));

	// INT_MAX results in 1024 characters left of the dot with radix 2
	// give the same space on the right side. safety checks are in place
	// unless someone finds a precise rule.
	char s[2048 + 3];
	const char* lastCharInString = s + sizeof(s) - 1;
	double x = v.uncheckedGetNumber();
	if (isnan(x) \|\| isinf(x))
	return JSValue::encode(jsString(exec, UString::number(x)));

	bool isNegative = x < 0.0;
	if (isNegative)
	x = -x;

	double integerPart = floor(x);
	char* decimalPoint = s + sizeof(s) / 2;

	// convert integer portion
	char* p = decimalPoint;
	double d = integerPart;
	do {
	int remainderDigit = static_cast<int>(fmod(d, radix));
	*--p = digits[remainderDigit];
	d /= radix;
	} while ((d <= -1.0 \|\| d >= 1.0) && s < p);

	if (isNegative)
	*--p = '-';
	char* startOfResultString = p;
	ASSERT(s <= startOfResultString);

	d = x - integerPart;
	p = decimalPoint;
	const double epsilon = 0.001; // TODO: guessed. base on radix ?
	bool hasFractionalPart = (d < -epsilon \|\| d > epsilon);
	if (hasFractionalPart) {
	*p++ = '.';
	do {
	d *= radix;
	const int digit = static_cast<int>(d);
	*p++ = digits[digit];
	d -= digit;
	} while ((d < -epsilon \|\| d > epsilon) && p < lastCharInString);
	}
	*p = '\0';
	ASSERT(p < s + sizeof(s));

	return JSValue::encode(jsString(exec, startOfResultString));
	}

	EncodedJSValue JSC_HOST_CALL numberProtoFuncToLocaleString(ExecState* exec)
	{
	JSValue thisValue = exec->hostThisValue();
	// FIXME: Not implemented yet.

	JSValue v = thisValue.getJSNumber();
	if (!v)
	return throwVMTypeError(exec);

	return JSValue::encode(jsString(exec, v.toString(exec)));
	}

	EncodedJSValue JSC_HOST_CALL numberProtoFuncValueOf(ExecState* exec)
	{
	JSValue thisValue = exec->hostThisValue();
	JSValue v = thisValue.getJSNumber();
	if (!v)
	return throwVMTypeError(exec);

	return JSValue::encode(v);
	}

	} // namespace JSC