Migrated source code from Simantics SVN

[simantics/platform.git] / bundles / org.simantics.scl.compiler / src / org / simantics / scl / compiler / internal / deriving / EqDeriver.java

diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/internal/deriving/EqDeriver.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/internal/deriving/EqDeriver.java
new file mode 100644 (file)
index 0000000..31c1837
--- /dev/null
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/internal/deriving/EqDeriver.java
@@ -0,0 +1,117 @@
+package org.simantics.scl.compiler.internal.deriving;
+
+import java.util.ArrayList;
+
+import org.simantics.scl.compiler.common.datatypes.Constructor;
+import org.simantics.scl.compiler.elaboration.errors.NotPatternException;
+import org.simantics.scl.compiler.elaboration.expressions.EApply;
+import org.simantics.scl.compiler.elaboration.expressions.EVar;
+import org.simantics.scl.compiler.elaboration.expressions.EVariable;
+import org.simantics.scl.compiler.elaboration.expressions.Expression;
+import org.simantics.scl.compiler.elaboration.expressions.Variable;
+import org.simantics.scl.compiler.elaboration.modules.TypeConstructor;
+import org.simantics.scl.compiler.environment.AmbiguousNameException;
+import org.simantics.scl.compiler.environment.Environment;
+import org.simantics.scl.compiler.environment.Environments;
+import org.simantics.scl.compiler.errors.ErrorLog;
+import org.simantics.scl.compiler.internal.parsing.declarations.DDerivingInstanceAst;
+import org.simantics.scl.compiler.internal.parsing.declarations.DInstanceAst;
+import org.simantics.scl.compiler.internal.parsing.declarations.DValueAst;
+import org.simantics.scl.compiler.internal.parsing.expressions.Expressions;
+import org.simantics.scl.compiler.internal.parsing.translation.ProcessedDInstanceAst;
+import org.simantics.scl.compiler.internal.parsing.translation.ValueRepository;
+import org.simantics.scl.compiler.internal.parsing.types.TVarAst;
+import org.simantics.scl.compiler.types.TCon;
+
+class EqDeriver implements InstanceDeriver {
+
+    @Override
+    public void derive(
+            ErrorLog errorLog,
+            Environment environment,
+            ArrayList<ProcessedDInstanceAst> instancesAst,
+            DDerivingInstanceAst der) {
+     // Analyze
+        if(der.types.length != 1) {
+            errorLog.log(der.location, "Invalid number of parameters to " + der.name);
+            return;
+        }
+        TVarAst headType = DerivingUtils.getHeadType(der.types[0]);
+        if(headType == null) {
+            errorLog.log(der.types[0].location, "Cannot derive Eq instance for the type " + headType + ".");
+            return;
+        }
+        TCon con;
+        try {
+            con = Environments.getTypeConstructorName(environment, headType.name);
+        } catch (AmbiguousNameException e1) {
+            errorLog.log(headType.location, e1.getMessage());
+            return;
+        }
+        if(con == null) {
+            errorLog.log(headType.location, "Couldn't resolve " + headType.name);
+            return;
+        }
+        TypeConstructor tcon = environment.getTypeConstructor(con);
+        if(tcon == null) {
+            errorLog.log(headType.location, "Didn't find type constructor for " + headType.name);
+            return;
+        }
+        if(tcon.isOpen) {
+            errorLog.log(headType.location, "Cannot derive instance for open data types.");
+            return;
+        }
+        
+        // Generate
+        DInstanceAst instanceAst = new DInstanceAst(der.location, der.context, der.name, der.types);
+        ValueRepository valueDefs = new ValueRepository();
+        for(Constructor constructor : tcon.constructors) {
+            int l = constructor.parameterTypes.length;
+            String[] par1 = new String[l];
+            String[] par2 = new String[l];
+            for(int i=0;i<l;++i) {
+                par1[i] = "a" + i;
+                par2[i] = "b" + i;
+            }
+            Expression lhs = new EApply(
+                    new EVar("=="),
+                    new EApply(new EVar(constructor.name.name), Expressions.vars(par1)),
+                    new EApply(new EVar(constructor.name.name), Expressions.vars(par2))
+                    );
+            Expression value = new EVar("True");
+            for(int i=l-1;i>=0;--i)
+                value = new EApply(
+                        new EVar("&&"),
+                        new EApply(
+                                new EVar("=="), 
+                                new EVar(par1[i]), 
+                                new EVar(par2[i])),
+                        value);
+            try {
+                DValueAst valueAst = new DValueAst(lhs, value);
+                valueAst.setLocationDeep(der.location);
+                valueDefs.add(valueAst);
+            } catch (NotPatternException e) {
+                errorLog.log(e.getExpression().location, "Not a pattern.");
+            }
+        }
+        {
+            Expression lhs = new EApply(
+                    new EVar("=="),
+                    new EVariable(new Variable("_")),
+                    new EVariable(new Variable("_")));
+            Expression value = new EVar("False");
+            try {
+                DValueAst valueAst = new DValueAst(lhs, value);
+                valueAst.setLocationDeep(der.location);
+                valueDefs.add(valueAst);
+                /*valueDefs.addAnnotation("==", new DAnnotationAst(new EVar("@private"), 
+                        Collections.<Expression>emptyList()));*/
+            } catch (NotPatternException e) {
+                errorLog.log(e.getExpression().location, "Not a pattern.");
+            }
+        }
+        instancesAst.add(new ProcessedDInstanceAst(instanceAst, valueDefs));
+    }
+
+}