1   /*
2    * SPDX-FileCopyrightText: none
3    * SPDX-License-Identifier: CC0-1.0
4    */
5   
6   package gov.nist.secauto.metaschema.core.metapath.function;
7   
8   import gov.nist.secauto.metaschema.core.qname.IEnhancedQName;
9   
10  import java.util.stream.Stream;
11  
12  import edu.umd.cs.findbugs.annotations.NonNull;
13  
14  public interface IFunctionLibrary {
15  
16    /**
17     * Retrieve the collection of function signatures in this library as a stream.
18     *
19     * @return a stream of function signatures
20     */
21    @NonNull
22    Stream<IFunction> stream();
23  
24    /**
25     * Determine if there is a function with the provided namespace qualified name
26     * that supports the signature of the provided {@code arity}.
27     *
28     * @param name
29     *          the namespace qualified name of a group of functions
30     * @param arity
31     *          the count of arguments for use in determining an argument signature
32     *          match
33     * @return {@code true} if a function signature matches or {@code false}
34     *         otherwise
35     */
36    default boolean hasFunction(@NonNull IEnhancedQName name, int arity) {
37      return getFunction(name, arity) != null;
38    }
39  
40    /**
41     * Retrieve the function with the provided namespace qualified name that
42     * supports the signature of the provided {@code arity}, if such a function
43     * exists.
44     *
45     * @param name
46     *          the namespace qualified name of a group of functions
47     * @param arity
48     *          the count of arguments for use in determining an argument signature
49     *          match
50     * @return the matching function or {@code null} if no match exists
51     */
52    IFunction getFunction(@NonNull IEnhancedQName name, int arity);
53  }