icuSources/i18n/visibledigits.h

   1 // © 2016 and later: Unicode, Inc. and others.
   2 // License & terms of use: http://www.unicode.org/copyright.html
   3 /*
   4 ******************************************************************************* * Copyright (C) 2015, International Business Machines
   5 * Corporation and others.  All Rights Reserved.
   6 *******************************************************************************
   7 * visibledigits.h
   8 *
   9 * created on: 2015jun20
  10 * created by: Travis Keep
  11 */
  12
  13 #ifndef __VISIBLEDIGITS_H__
  14 #define __VISIBLEDIGITS_H__
  15
  16 #include "unicode/utypes.h"
  17
  18 #if !UCONFIG_NO_FORMATTING
  19
  20 #include "unicode/uobject.h"
  21
  22 #include "charstr.h"
  23 #include "digitinterval.h"
  24
  25 U_NAMESPACE_BEGIN
  26
  27 class DigitList;
  28
  29 /**
  30  * VisibleDigits represents the digits visible for formatting.
  31  * Once initialized using a FixedPrecision instance, VisibleDigits instances
  32  * remain unchanged until they are initialized again. A VisibleDigits with
  33  * a numeric value equal to 3.0 could be "3", "3.0", "3.00" or even "003.0"
  34  * depending on settings of the FixedPrecision instance used to initialize it.
  35  */
  36 class U_I18N_API VisibleDigits : public UMemory {
  37 public:
  38     VisibleDigits() : fExponent(0), fFlags(0), fAbsIntValue(0), fAbsIntValueSet(FALSE), fAbsDoubleValue(0.0), fAbsDoubleValueSet(FALSE) { }
  39
  40     UBool isNegative() const;
  41     UBool isNaN() const;
  42     UBool isInfinite() const;
  43     UBool isNaNOrInfinity() const;
  44
  45     /**
  46      * Gets the digit at particular exponent, if number is 987.6, then
  47      * getDigit(2) == 9 and gitDigit(0) == 7 and gitDigit(-1) == 6.
  48      * If isNaN() or isInfinity() return TRUE, then the result of this
  49      * function is undefined.
  50      */
  51     int32_t getDigitByExponent(int32_t digitPos) const;
  52
  53     /**
  54      * Returns the digit interval which indicates the leftmost and rightmost
  55      * position of this instance.
  56      * If isNaN() or isInfinity() return TRUE, then the result of this
  57      * function is undefined.
  58      */
  59     const DigitInterval &getInterval() const { return fInterval; }
  60
  61     /**
  62      * Gets the parameters needed to create a FixedDecimal.
  63      */
  64     void getFixedDecimal(double &source, int64_t &intValue, int64_t &f, int64_t &t, int32_t &v, UBool &hasIntValue) const;
  65
  66
  67 private:
  68     /**
  69      * The digits, least significant first. Both the least and most
  70      * significant digit in this list are non-zero; however, digits in the
  71      * middle may be zero. This field contains values between (char) 0, and
  72      * (char) 9 inclusive.
  73      */
  74     CharString fDigits;
  75
  76     /**
  77      * The range of displayable digits. This field is needed to account for
  78      * any leading and trailing zeros which are not stored in fDigits.
  79      */
  80     DigitInterval fInterval;
  81
  82     /**
  83      * The exponent value of the least significant digit in fDigits. For
  84      * example, fExponent = 2 and fDigits = {7, 8, 5} represents 58700.
  85      */
  86     int32_t fExponent;
  87
  88     /**
  89      * Contains flags such as NaN, Inf, and negative.
  90      */
  91     int32_t fFlags;
  92
  93     /**
  94      * Contains the absolute value of the digits left of the decimal place
  95      * if fAbsIntValueSet is TRUE
  96      */
  97     int64_t fAbsIntValue;
  98
  99     /**
 100      * Indicates whether or not fAbsIntValue is set.
 101      */
 102     UBool fAbsIntValueSet;
 103
 104     /**
 105      * Contains the absolute value of the value this instance represents
 106      * if fAbsDoubleValueSet is TRUE
 107      */
 108     double fAbsDoubleValue;
 109
 110     /**
 111      * Indicates whether or not fAbsDoubleValue is set.
 112      */
 113     UBool fAbsDoubleValueSet;
 114
 115     void setNegative();
 116     void setNaN();
 117     void setInfinite();
 118     void clear();
 119     double computeAbsDoubleValue() const;
 120     UBool isOverMaxDigits() const;
 121
 122     VisibleDigits(const VisibleDigits &);
 123     VisibleDigits &operator=(const VisibleDigits &);
 124
 125     friend class FixedPrecision;
 126     friend class VisibleDigitsWithExponent;
 127 };
 128
 129 /**
 130  * A VisibleDigits with a possible exponent.
 131  */
 132 class U_I18N_API VisibleDigitsWithExponent : public UMemory {
 133 public:
 134     VisibleDigitsWithExponent() : fHasExponent(FALSE) { }
 135     const VisibleDigits &getMantissa() const { return fMantissa; }
 136     const VisibleDigits *getExponent() const {
 137         return fHasExponent ? &fExponent : NULL;
 138     }
 139     void clear() {
 140         fMantissa.clear();
 141         fExponent.clear();
 142         fHasExponent = FALSE;
 143     }
 144     UBool isNegative() const { return fMantissa.isNegative(); }
 145     UBool isNaN() const { return fMantissa.isNaN(); }
 146     UBool isInfinite() const { return fMantissa.isInfinite(); }
 147 private:
 148     VisibleDigitsWithExponent(const VisibleDigitsWithExponent &);
 149     VisibleDigitsWithExponent &operator=(
 150         const VisibleDigitsWithExponent &);
 151     VisibleDigits fMantissa;
 152     VisibleDigits fExponent;
 153     UBool fHasExponent;
 154
 155     friend class ScientificPrecision;
 156     friend class FixedPrecision;
 157 };
 158
 159
 160 U_NAMESPACE_END
 161 #endif /* #if !UCONFIG_NO_FORMATTING */
 162 #endif  // __VISIBLEDIGITS_H__