chromium/third_party/icu/source/i18n/units_converter.h

// © 2020 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html

#include "unicode/utypes.h"

#if !UCONFIG_NO_FORMATTING
#ifndef __UNITS_CONVERTER_H__
#define __UNITS_CONVERTER_H__

#include "cmemory.h"
#include "measunit_impl.h"
#include "unicode/errorcode.h"
#include "unicode/stringpiece.h"
#include "unicode/uobject.h"
#include "units_converter.h"
#include "units_data.h"

U_NAMESPACE_BEGIN
namespace units {

/* Internal Structure */

// Constants corresponding to unitConstants in CLDR's units.xml.
enum Constants { … };

// These values are a hard-coded subset of unitConstants in the units
// resources file. A unit test checks that all constants in the resource
// file are at least recognised by the code. Derived constants' values or
// hard-coded derivations are not checked.
// In ICU4J, these constants live in UnitConverter.Factor.getConversionRate().
static const double constantsValues[CONSTANTS_COUNT] = …;

Signum;

/* Represents a conversion factor */
struct U_I18N_API Factor { … };

struct U_I18N_API ConversionInfo { … };

/*
 * Adds a single factor element to the `Factor`. e.g "ft3m", "2.333" or "cup2m3". But not "cup2m3^3".
 */
void U_I18N_API addSingleFactorConstant(StringPiece baseStr, int32_t power, Signum sigNum,
                                        Factor &factor, UErrorCode &status);

/**
 * Represents the conversion rate between `source` and `target`.
 */
struct U_I18N_API ConversionRate : public UMemory { … };

enum Convertibility { … };

MeasureUnitImpl U_I18N_API extractCompoundBaseUnit(const MeasureUnitImpl &source,
                                                   const ConversionRates &conversionRates,
                                                   UErrorCode &status);

/**
 * Check if the convertibility between `source` and `target`.
 * For example:
 *    `meter` and `foot` are `CONVERTIBLE`.
 *    `meter-per-second` and `second-per-meter` are `RECIPROCAL`.
 *    `meter` and `pound` are `UNCONVERTIBLE`.
 *
 * NOTE:
 *    Only works with SINGLE and COMPOUND units. If one of the units is a
 *    MIXED unit, an error will occur. For more information, see UMeasureUnitComplexity.
 */
Convertibility U_I18N_API extractConvertibility(const MeasureUnitImpl &source,
                                                const MeasureUnitImpl &target,
                                                const ConversionRates &conversionRates,
                                                UErrorCode &status);

/**
 * Converts from a source `MeasureUnit` to a target `MeasureUnit`.
 *
 * NOTE:
 *    Only works with SINGLE and COMPOUND units. If one of the units is a
 *    MIXED unit, an error will occur. For more information, see UMeasureUnitComplexity.
 */
class U_I18N_API UnitsConverter : public UMemory { … };

} // namespace units
U_NAMESPACE_END

#endif //__UNITS_CONVERTER_H__

#endif /* #if !UCONFIG_NO_FORMATTING */