YGValue.h

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/*
 * Copyright (c) Meta Platforms, Inc. and affiliates.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 */
 
#pragma once
 
#include <stdbool.h>
 
#include <yoga/YGEnums.h>
#include <yoga/YGMacros.h>
 
#ifdef __cplusplus
#include <limits>
constexpr float YGUndefined = std::numeric_limits<float>::quiet_NaN();
#else
#include <math.h>
#define YGUndefined NAN
#endif
 
YG_EXTERN_C_BEGIN
 
typedef struct YGValue {
  float value;
  YGUnit unit;
} YGValue;
 
YG_EXPORT extern const YGValue YGValueAuto;
 
YG_EXPORT extern const YGValue YGValueUndefined;
 
YG_EXPORT extern const YGValue YGValueZero;
 
YG_EXPORT bool YGFloatIsUndefined(float value);
 
YG_EXTERN_C_END
 
// Equality operators for comparison of YGValue in C++
#ifdef __cplusplus
inline bool operator==(const YGValue& lhs, const YGValue& rhs) {
  if (lhs.unit != rhs.unit) {
    return false;
  }
 
  switch (lhs.unit) {
    case YGUnitUndefined:
    case YGUnitAuto:
    case YGUnitFitContent:
    case YGUnitMaxContent:
    case YGUnitStretch:
      return true;
    case YGUnitPoint:
    case YGUnitPercent:
      return lhs.value == rhs.value;
    default:
      return false;
  }
}
 
inline YGValue operator-(const YGValue& value) {
  return {-value.value, value.unit};
}
#endif