better patterns: assign variable values

src/main/java/org/programsnail/truffle_lama/nodes/controlflow/LamaCaseNode.java

@@ -31,7 +31,9 @@ public final class LamaCaseNode extends LamaExpressionNode {
     public Object executeGeneric(VirtualFrame frame) throws UnexpectedResultException {
         Object value = this.valueNode.executeGeneric(frame);
         for (int i = 0; i < this.patterns.length; ++i) {
-            if (this.patterns[i].match(value)) { // TODO: special case for name binding ??
+            var patternMatch = this.patterns[i].match(value);
+            if (patternMatch.isPresent()) {
+                patternMatch.get().assignVariablesIn(frame);
                 return this.exprNodes[i].executeGeneric(frame);
             }
         }

src/main/java/org/programsnail/truffle_lama/nodes/pattern/LamaArrayPattern.java

@@ -2,6 +2,8 @@ package org.programsnail.truffle_lama.nodes.pattern;
 
 import org.programsnail.truffle_lama.runtime.LamaArray;
 
+import java.util.Optional;
+
 public final class LamaArrayPattern extends LamaPattern {
     private final LamaPattern[] elements;
 
@@ -10,18 +12,19 @@ public final class LamaArrayPattern extends LamaPattern {
     }
 
     @Override
-    public boolean match(Object object) {
-        if (!(object instanceof LamaArray array)) {
-            return false;
-        }
-        if (elements.length != array.getLength()) {
-            return false;
+    public Optional<PatternMatch> match(Object object) {
+        if (!(object instanceof LamaArray array) || elements.length != array.getLength()) {
+            return Optional.empty();
         }
+
+        PatternMatch patternMatch = new PatternMatch();
         for (int i = 0; i < elements.length; ++i) {
-            if (!elements[i].match(array.readAt(i))) {
-                return false;
+            var currentMatch = elements[i].match(array.readAt(i));
+            if (currentMatch.isEmpty()) {
+                return Optional.empty();
             }
+            patternMatch.extendWith(currentMatch.get());
         }
-        return true;
+        return Optional.of(patternMatch);
     }
 }

src/main/java/org/programsnail/truffle_lama/nodes/pattern/LamaArrayTagPattern.java

@@ -2,9 +2,11 @@ package org.programsnail.truffle_lama.nodes.pattern;
 
 import org.programsnail.truffle_lama.runtime.LamaArray;
 
+import java.util.Optional;
+
 public final class LamaArrayTagPattern extends LamaPattern {
     @Override
-    public boolean match(Object object) {
-        return object instanceof LamaArray;
+    public Optional<PatternMatch> match(Object object) {
+        return optionalOfBoolean(object instanceof LamaArray);
     }
 }

src/main/java/org/programsnail/truffle_lama/nodes/pattern/LamaBoxedPattern.java

@@ -4,9 +4,11 @@ import com.oracle.truffle.api.strings.TruffleString;
 import org.programsnail.truffle_lama.runtime.LamaArrayLike;
 import org.programsnail.truffle_lama.runtime.LamaSexp;
 
+import java.util.Optional;
+
 public final class LamaBoxedPattern extends LamaPattern {
     @Override
-    public boolean match(Object object) {
-        return object instanceof TruffleString || object instanceof LamaArrayLike; // includes array and sexp
+    public Optional<PatternMatch> match(Object object) {
+        return optionalOfBoolean(object instanceof TruffleString || object instanceof LamaArrayLike); // includes array and sexp
     }
 }

src/main/java/org/programsnail/truffle_lama/nodes/pattern/LamaClosureTagPattern.java

@@ -2,9 +2,11 @@ package org.programsnail.truffle_lama.nodes.pattern;
 
 import org.programsnail.truffle_lama.FunctionObject;
 
+import java.util.Optional;
+
 public final class LamaClosureTagPattern extends LamaPattern {
     @Override
-    public boolean match(Object object) {
-        return object instanceof FunctionObject; // TODO: check
+    public Optional<PatternMatch> match(Object object) {
+        return optionalOfBoolean(object instanceof FunctionObject); // TODO: check
     }
 }

src/main/java/org/programsnail/truffle_lama/nodes/pattern/LamaConstPattern.java

@@ -2,6 +2,8 @@ package org.programsnail.truffle_lama.nodes.pattern;
 
 import org.programsnail.truffle_lama.runtime.LamaArray;
 
+import java.util.Optional;
+
 public final class LamaConstPattern extends LamaPattern {
     private final long value;
 
@@ -10,7 +12,7 @@ public final class LamaConstPattern extends LamaPattern {
     }
 
     @Override
-    public boolean match(Object object) {
-        return (object instanceof Integer other) && other == value;
+    public Optional<PatternMatch> match(Object object) {
+        return optionalOfBoolean((object instanceof Integer other) && other == value);
     }
 }

src/main/java/org/programsnail/truffle_lama/nodes/pattern/LamaNamedPattern.java

@@ -1,5 +1,18 @@
 package org.programsnail.truffle_lama.nodes.pattern;
 
+import com.oracle.truffle.api.frame.VirtualFrame;
+
+import java.util.Optional;
+
 public final class LamaNamedPattern extends LamaPattern {
-    // TODO: return var assignment in som way
+    private final int id;
+
+    public LamaNamedPattern(int id, VirtualFrame frame) {
+        this.id = id;
+    }
+
+    @Override
+    public Optional<PatternMatch> match(Object object) {
+        return Optional.of(new PatternMatch(id, object));
+    }
 }

src/main/java/org/programsnail/truffle_lama/nodes/pattern/LamaPattern.java

@@ -1,5 +1,11 @@
 package org.programsnail.truffle_lama.nodes.pattern;
 
+import java.util.Optional;
+
 public abstract class LamaPattern {
-    public abstract boolean match(Object object);
+    public abstract Optional<PatternMatch> match(Object object);
+
+    protected static Optional<PatternMatch> optionalOfBoolean(boolean value) {
+        return value ? Optional.of(new PatternMatch()) : Optional.empty();
+    }
 }

src/main/java/org/programsnail/truffle_lama/nodes/pattern/LamaSexpPattern.java

@@ -1,4 +1,33 @@
 package org.programsnail.truffle_lama.nodes.pattern;
 
+import com.oracle.truffle.api.strings.TruffleString;
+import org.programsnail.truffle_lama.runtime.LamaSexp;
+
+import java.util.Optional;
+
 public final class LamaSexpPattern extends LamaPattern {
+    private final TruffleString tag;
+    private final LamaPattern[] elements;
+
+    public LamaSexpPattern(TruffleString tag, LamaPattern[] elements) {
+        this.tag = tag;
+        this.elements = elements;
+    }
+
+    @Override
+    public Optional<PatternMatch> match(Object object) {
+        if (!(object instanceof LamaSexp sexp) || tag != sexp.getTag() || elements.length != sexp.getLength()) {
+            return Optional.empty();
+        }
+
+        PatternMatch patternMatch = new PatternMatch();
+        for (int i = 0; i < elements.length; ++i) {
+            var currentMatch = elements[i].match(sexp.readAt(i));
+            if (currentMatch.isEmpty()) {
+                return Optional.empty();
+            }
+            patternMatch.extendWith(currentMatch.get());
+        }
+        return Optional.of(patternMatch);
+    }
 }

src/main/java/org/programsnail/truffle_lama/nodes/pattern/LamaSexpTagPattern.java

@@ -2,9 +2,11 @@ package org.programsnail.truffle_lama.nodes.pattern;
 
 import org.programsnail.truffle_lama.runtime.LamaSexp;
 
+import java.util.Optional;
+
 public final class LamaSexpTagPattern extends LamaPattern {
     @Override
-    public boolean match(Object object) {
-        return object instanceof LamaSexp;
+    public Optional<PatternMatch> match(Object object) {
+        return optionalOfBoolean(object instanceof LamaSexp);
     }
 }

src/main/java/org/programsnail/truffle_lama/nodes/pattern/LamaStringPattern.java

@@ -2,6 +2,8 @@ package org.programsnail.truffle_lama.nodes.pattern;
 
 import com.oracle.truffle.api.strings.TruffleString;
 
+import java.util.Optional;
+
 public final class LamaStringPattern extends LamaPattern {
     private final TruffleString value;
 
@@ -10,7 +12,7 @@ public final class LamaStringPattern extends LamaPattern {
     }
 
     @Override
-    public boolean match(Object object) {
-        return (object instanceof TruffleString other) && other == value;
+    public Optional<PatternMatch> match(Object object) {
+        return optionalOfBoolean((object instanceof TruffleString other) && other == value);
     }
 }

src/main/java/org/programsnail/truffle_lama/nodes/pattern/LamaStringTagPattern.java

@@ -2,9 +2,11 @@ package org.programsnail.truffle_lama.nodes.pattern;
 
 import com.oracle.truffle.api.strings.TruffleString;
 
+import java.util.Optional;
+
 public final class LamaStringTagPattern extends LamaPattern {
     @Override
-    public boolean match(Object object) {
-        return object instanceof TruffleString;
+    public Optional<PatternMatch> match(Object object) {
+        return optionalOfBoolean(object instanceof TruffleString);
     }
 }

src/main/java/org/programsnail/truffle_lama/nodes/pattern/LamaUnBoxedPattern.java

@@ -1,8 +1,10 @@
 package org.programsnail.truffle_lama.nodes.pattern;
 
+import java.util.Optional;
+
 public final class LamaUnBoxedPattern extends LamaPattern {
     @Override
-    public boolean match(Object object) {
-        return object instanceof Integer; // TODO: does work with int ??
+    public Optional<PatternMatch> match(Object object) {
+        return optionalOfBoolean(object instanceof Integer); // TODO: does work with int ??
     }
 }

src/main/java/org/programsnail/truffle_lama/nodes/pattern/LamaWildcardPattern.java

@@ -1,8 +1,10 @@
 package org.programsnail.truffle_lama.nodes.pattern;
 
+import java.util.Optional;
+
 public final class LamaWildcardPattern extends LamaPattern {
     @Override
-    public boolean match(Object object) {
-        return true;
+    public Optional<PatternMatch> match(Object object) {
+        return optionalOfBoolean(true);
     }
 }

src/main/java/org/programsnail/truffle_lama/nodes/pattern/PatternMatch.java

@@ -0,0 +1,48 @@
+package org.programsnail.truffle_lama.nodes.pattern;
+
+import com.oracle.truffle.api.frame.VirtualFrame;
+import org.antlr.v4.runtime.misc.Pair;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public final class PatternMatch {
+    public static final class MatchElem {
+        public final int id;
+        public final Object object;
+
+        public MatchElem(int id, Object object) {
+            this.id = id;
+            this.object = object;
+        }
+    }
+
+    private final List<MatchElem> matches;
+
+    public PatternMatch() {
+        this.matches = new ArrayList<>();
+    }
+
+    public PatternMatch(Integer id, Object object) {
+        this.matches = new ArrayList<>();
+        addMatch(id, object);
+    }
+
+    public PatternMatch(List<MatchElem> matches) {
+        this.matches = matches;
+    }
+
+    public void addMatch(Integer id, Object object) {
+        this.matches.addLast(new MatchElem(id, object));
+    }
+
+    public void extendWith(PatternMatch other) {
+        matches.addAll(other.matches);
+    }
+
+    public void assignVariablesIn(VirtualFrame frame) {
+        for (var match : matches) {
+            frame.setObject(match.id, match.object);
+        }
+    }
+}

src/main/java/org/programsnail/truffle_lama/runtime/LamaSexp.java

@@ -1,18 +1,20 @@
 package org.programsnail.truffle_lama.runtime;
 
-public final class LamaSexp extends LamaArrayLike {
-    private String tag;
+import com.oracle.truffle.api.strings.TruffleString;
 
-    public String getTag() {
+public final class LamaSexp extends LamaArrayLike {
+    private TruffleString tag;
+
+    public TruffleString getTag() {
         return tag;
     }
 
-    public LamaSexp(String tag, Object[] elements) {
+    public LamaSexp(TruffleString tag, Object[] elements) {
         super(elements);
         this.tag = tag;
     }
 
-    LamaSexp(String tag, int length) {
+    LamaSexp(TruffleString tag, int length) {
         super(length);
         this.tag = tag;
     }