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// Copyright 2025 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef THIRD_PARTY_BLINK_RENDERER_CORE_CSS_KLEENE_VALUE_H_
#define THIRD_PARTY_BLINK_RENDERER_CORE_CSS_KLEENE_VALUE_H_
namespace blink {
// See Kleene 3-valued logic
//
// https://drafts.csswg.org/mediaqueries-4/#evaluating
enum class KleeneValue {
kTrue,
kFalse,
kUnknown,
};
inline KleeneValue KleeneNot(KleeneValue a) {
switch (a) {
case KleeneValue::kTrue:
return KleeneValue::kFalse;
case KleeneValue::kFalse:
return KleeneValue::kTrue;
case KleeneValue::kUnknown:
return KleeneValue::kUnknown;
}
}
inline KleeneValue KleeneOr(KleeneValue a, KleeneValue b) {
switch (a) {
case KleeneValue::kTrue:
return KleeneValue::kTrue;
case KleeneValue::kFalse:
return b;
case KleeneValue::kUnknown:
return (b == KleeneValue::kTrue) ? KleeneValue::kTrue
: KleeneValue::kUnknown;
}
}
inline KleeneValue KleeneAnd(KleeneValue a, KleeneValue b) {
switch (a) {
case KleeneValue::kTrue:
return b;
case KleeneValue::kFalse:
return KleeneValue::kFalse;
case KleeneValue::kUnknown:
return (b == KleeneValue::kFalse) ? KleeneValue::kFalse
: KleeneValue::kUnknown;
}
}
} // namespace blink
#endif // THIRD_PARTY_BLINK_RENDERER_CORE_CSS_KLEENE_VALUE_H_
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