001    /*
002     * Copyright 2010-2013 JetBrains s.r.o.
003     *
004     * Licensed under the Apache License, Version 2.0 (the "License");
005     * you may not use this file except in compliance with the License.
006     * You may obtain a copy of the License at
007     *
008     * http://www.apache.org/licenses/LICENSE-2.0
009     *
010     * Unless required by applicable law or agreed to in writing, software
011     * distributed under the License is distributed on an "AS IS" BASIS,
012     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013     * See the License for the specific language governing permissions and
014     * limitations under the License.
015     */
016    
017    package org.jetbrains.jet.lang.types.checker;
018    
019    import org.jetbrains.annotations.NotNull;
020    import org.jetbrains.jet.lang.types.JetType;
021    import org.jetbrains.jet.lang.types.TypeConstructor;
022    
023    public class JetTypeChecker {
024    
025        public interface TypeConstructorEquality {
026            boolean equals(@NotNull TypeConstructor a, @NotNull TypeConstructor b);
027        }
028    
029        public static final JetTypeChecker DEFAULT = new JetTypeChecker(new TypeCheckingProcedure(new TypeCheckerTypingConstraints()));
030    
031        @NotNull
032        public static JetTypeChecker withAxioms(@NotNull final TypeConstructorEquality equalityAxioms) {
033            return new JetTypeChecker(new TypeCheckingProcedure(new TypeCheckerTypingConstraints() {
034                @Override
035                public boolean assertEqualTypeConstructors(@NotNull TypeConstructor constructor1, @NotNull TypeConstructor constructor2) {
036                    return constructor1.equals(constructor2) || equalityAxioms.equals(constructor1, constructor2);
037                }
038            }));
039        }
040    
041        private final TypeCheckingProcedure procedure;
042    
043        private JetTypeChecker(@NotNull TypeCheckingProcedure procedure) {
044            this.procedure = procedure;
045        }
046    
047        public boolean isSubtypeOf(@NotNull JetType subtype, @NotNull JetType supertype) {
048            return procedure.isSubtypeOf(subtype, supertype);
049        }
050    
051        public boolean equalTypes(@NotNull JetType a, @NotNull JetType b) {
052            return procedure.equalTypes(a, b);
053        }
054    }