/interpreter/tags/reactive-pattern-matching/src/edu/vub/at/objects/natives/NATPatternType.java

  1/**
  2 * AmbientTalk/2 Project
  3 * NATPatternType.java created on Jul 4, 2008 at 10:21:18 AM
  4 * (c) Programming Technology Lab, 2006 - 2007
  5 * Authors: Tom Van Cutsem & Stijn Mostinckx
  6 * 
  7 * Permission is hereby granted, free of charge, to any person
  8 * obtaining a copy of this software and associated documentation
  9 * files (the "Software"), to deal in the Software without
 10 * restriction, including without limitation the rights to use,
 11 * copy, modify, merge, publish, distribute, sublicense, and/or
 12 * sell copies of the Software, and to permit persons to whom the
 13 * Software is furnished to do so, subject to the following
 14 * conditions:
 15 *
 16 * The above copyright notice and this permission notice shall be
 17 * included in all copies or substantial portions of the Software.
 18 *
 19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 20 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
 21 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 22 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
 23 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
 24 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 25 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 26 * OTHER DEALINGS IN THE SOFTWARE.
 27 */
 28package edu.vub.at.objects.natives;
 29
 30import edu.vub.at.eval.Evaluator;
 31import edu.vub.at.exceptions.InterpreterException;
 32import edu.vub.at.exceptions.XArityMismatch;
 33import edu.vub.at.exceptions.XIllegalArgument;
 34import edu.vub.at.objects.ATClosure;
 35import edu.vub.at.objects.ATContext;
 36import edu.vub.at.objects.ATMethod;
 37import edu.vub.at.objects.ATObject;
 38import edu.vub.at.objects.ATTable;
 39import edu.vub.at.objects.ATTypeTag;
 40import edu.vub.at.objects.coercion.NativeTypeTags;
 41import edu.vub.at.objects.grammar.ATSymbol;
 42import edu.vub.at.objects.natives.grammar.AGApplication;
 43import edu.vub.at.signals.natives.NATLiftedBehavior;
 44
 45/**
 46 * @author smostinc
 47 *
 48 */
 49public class NATPatternType extends NATTypeTag implements ATClosure {
 50
 51	ATTable parameters;
 52	
 53	public NATPatternType(AGApplication pattern) throws InterpreterException {
 54		super(pattern.base_function().asSymbol(), NATTable.EMPTY);
 55		
 56		parameters = pattern.base_arguments();
 57	}
 58	
 59	public NATPatternType(ATSymbol typeName, ATTable typeArgs) {
 60		super(typeName, NATTable.EMPTY);
 61		
 62		parameters = typeArgs;
 63	}
 64	
 65	public ATObject base_apply(ATTable theArguments) throws InterpreterException {
 66		boolean		shouldBeLifted	= false;
 67		ATObject[] 	argumentsArray 	= theArguments.asNativeTable().elements_;
 68
 69		for (int argIndex = 0; argIndex < argumentsArray.length; argIndex++) {
 70			ATObject currentArgument = argumentsArray[argIndex];
 71		
 72			if (currentArgument.isBehavior()) {
 73				shouldBeLifted = true;
 74
 75				break;
 76			}
 77		}
 78
 79		if(shouldBeLifted) {
 80			return NATLiftedBehavior.fromClosure(this, argumentsArray);
 81		} // else
 82
 83		NATObject thePatternObject = new NATObject(new ATTypeTag[] { this, NativeTypeTags._ISOLATE_ });
 84		
 85		ATObject[] parameters = this.parameters.asNativeTable().elements_;
 86		ATObject[] arguments  = theArguments.asNativeTable().elements_;
 87		
 88		if(parameters.length != arguments.length)
 89			throw new XArityMismatch(typeName_.toString(), parameters.length, arguments.length);
 90		
 91		
 92		for (int i = 0; i < arguments.length; i++) {
 93			ATObject theValue = (ATObject) arguments[i];
 94			ATSymbol theName  = (ATSymbol) parameters[i];
 95			
 96			thePatternObject.meta_defineField(theName, theValue);
 97		}
 98		
 99		return thePatternObject;
100		
101	}
102	
103	public ATObject base_unapply(ATObject thePatternObject) throws InterpreterException {
104		if(! thePatternObject.meta_isTaggedAs(this).asNativeBoolean().javaValue)
105			throw new XIllegalArgument("Asked to unapply " + this + " on an object which does not have the proper type tag");
106		
107		ATObject[] parameters = this.parameters.asNativeTable().elements_;
108		ATObject[] arguments  = new ATObject[parameters.length];
109		
110		for (int i = 0; i < arguments.length; i++) {
111			ATSymbol theName  = (ATSymbol) parameters[i];
112			ATObject theValue = thePatternObject.meta_invokeField(thePatternObject, theName);
113			
114			arguments[i] = theValue;
115		}
116		
117		return NATTable.atValue(arguments);
118		
119	}
120	
121    public ATTable meta_typeTags() throws InterpreterException {
122    	return NATTable.of(NativeTypeTags._TYPETAG_, NativeTypeTags._ISOLATE_, NativeTypeTags._CLOSURE_);
123    }
124    
125    
126    // BOGUS METHODS
127    
128	public ATObject base_applyInScope(ATTable args, ATObject scope)
129			throws InterpreterException {
130		// TODO Auto-generated method stub
131		return null;
132	}
133
134	public ATContext base_context() throws InterpreterException {
135		return new NATContext(Evaluator.getGlobalLexicalScope(), this);
136	}
137
138	public ATObject base_escape() throws InterpreterException {
139		// TODO Auto-generated method stub
140		return null;
141	}
142
143	public ATMethod base_method() throws InterpreterException {
144		// TODO Auto-generated method stub
145		return null;
146	}
147
148	public ATObject base_whileTrue_(ATClosure body) throws InterpreterException {
149		// TODO Auto-generated method stub
150		return null;
151	}
152	
153	public ATClosure asClosure() throws InterpreterException {
154		return this;
155	}
156}