CalculationValue.cpp   [plain text]

/*
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#include "config.h"
#include "CalculationValue.h"

#include <limits>

namespace WebCore {

float CalcExpressionBinaryOperation::evaluate(float maxValue) const
{
    float left = m_leftSide->evaluate(maxValue);
    float right = m_rightSide->evaluate(maxValue);
    switch (m_operator) {
    case CalcAdd:
        return left + right;
    case CalcSubtract:
        return left - right;
    case CalcMultiply:
        return left * right;
    case CalcDivide:
        if (!right)
            return std::numeric_limits<float>::quiet_NaN();
        return left / right;
    }
    ASSERT_NOT_REACHED();
    return std::numeric_limits<float>::quiet_NaN();
}

PassRefPtr<CalculationValue> CalculationValue::create(PassOwnPtr<CalcExpressionNode> value, CalculationPermittedValueRange range)
{
    return adoptRef(new CalculationValue(value, range));
}

float CalculationValue::evaluate(float maxValue) const
{
    float result = m_value->evaluate(maxValue);
    // FIXME calc https://webkit.org/b/80411 : result is NaN when there is a division 
    // by zero which isn't found at parse time. 
    if (isnan(result))
        return 0;
    return m_isNonNegative && result < 0 ? 0 : result;
}

} // namespace WebCore