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 * (b) any piece of software and/or hardware listed in the lrgrwrks.txt file if
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package com.oracle.truffle.sl.runtime;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.IdentityHashMap;
import java.util.List;
import java.util.Map;

import com.oracle.truffle.api.RootCallTarget;
import com.oracle.truffle.api.CompilerDirectives.TruffleBoundary;
import com.oracle.truffle.api.interop.TruffleObject;
import com.oracle.truffle.api.source.Source;
import com.oracle.truffle.sl.SLLanguage;
import com.oracle.truffle.sl.parser.SimpleLanguageParser;

Manages the mapping from function names to function objects. /**
 * Manages the mapping from function names to {@link SLFunction function objects}.
 */
public final class SLFunctionRegistry {

    private final SLLanguage language;
    private final FunctionsObject functionsObject = new FunctionsObject();
    private final Map<Map<String, RootCallTarget>, Void> registeredFunctions = new IdentityHashMap<>();

    public SLFunctionRegistry(SLLanguage language) {
        this.language = language;
    }

    
Returns the canonical SLFunction object for the given name. If it does not exist yet, it is created. /**
     * Returns the canonical {@link SLFunction} object for the given name. If it does not exist yet,
     * it is created.
     */
    @TruffleBoundary
    public SLFunction lookup(String name, boolean createIfNotPresent) {
        SLFunction result = functionsObject.functions.get(name);
        if (result == null && createIfNotPresent) {
            result = new SLFunction(language, name);
            functionsObject.functions.put(name, result);
        }
        return result;
    }

    
Associates the SLFunction with the given name with the given implementation root node. If the function did not exist before, it defines the function. If the function existed before, it redefines the function and the old implementation is discarded. /**
     * Associates the {@link SLFunction} with the given name with the given implementation root
     * node. If the function did not exist before, it defines the function. If the function existed
     * before, it redefines the function and the old implementation is discarded.
     */
    SLFunction register(String name, RootCallTarget callTarget) {
        SLFunction result = functionsObject.functions.get(name);
        if (result == null) {
            result = new SLFunction(callTarget);
            functionsObject.functions.put(name, result);
        } else {
            result.setCallTarget(callTarget);
        }
        return result;
    }

    
Registers a map of functions. The once registered map must not change in order to allow to
cache the registration for the entire map. If the map is changed after registration the
functions might not get registered.
/**
     * Registers a map of functions. The once registered map must not change in order to allow to
     * cache the registration for the entire map. If the map is changed after registration the
     * functions might not get registered.
     */
    @TruffleBoundary
    public void register(Map<String, RootCallTarget> newFunctions) {
        if (registeredFunctions.containsKey(newFunctions)) {
            return;
        }
        for (Map.Entry<String, RootCallTarget> entry : newFunctions.entrySet()) {
            register(entry.getKey(), entry.getValue());
        }
        registeredFunctions.put(newFunctions, null);
    }

    public void register(Source newFunctions) {
        register(SimpleLanguageParser.parseSL(language, newFunctions));
    }

    public SLFunction getFunction(String name) {
        return functionsObject.functions.get(name);
    }

    
Returns the sorted list of all functions, for printing purposes only.
/**
     * Returns the sorted list of all functions, for printing purposes only.
     */
    public List<SLFunction> getFunctions() {
        List<SLFunction> result = new ArrayList<>(functionsObject.functions.values());
        Collections.sort(result, new Comparator<SLFunction>() {
            public int compare(SLFunction f1, SLFunction f2) {
                return f1.toString().compareTo(f2.toString());
            }
        });
        return result;
    }

    public TruffleObject getFunctionsObject() {
        return functionsObject;
    }

}