package org.checkerframework.checker.index.qual;
import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
import org.checkerframework.framework.qual.PolymorphicQualifier;
/**
* A polymorphic qualifier for the Lower Bound and Upper Bound type systems.
*
* <p>Writing {@code @PolyIndex} is equivalent to writing {@link PolyUpperBound @PolyUpperBound}
* {@link PolyLowerBound @PolyLowerBound}, and that is how it is treated internally by the checker.
* Thus, if you write an {@code @PolyIndex} annotation, you might see warnings about
* {@code @PolyUpperBound} or {@code @PolyLowerBound}.
*
* @checker_framework.manual #index-checker Index Checker
* @checker_framework.manual #qualifier-polymorphism Qualifier polymorphism
* @see PolyUpperBound
* @see PolyLowerBound
*/
@Documented
@Target({ElementType.TYPE_USE, ElementType.TYPE_PARAMETER})
@Retention(RetentionPolicy.RUNTIME)
@PolymorphicQualifier
public @interface PolyIndex {}