bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/internal/deriving/ShowDeriver.java

   1 package org.simantics.scl.compiler.internal.deriving;
   2
   3 import java.util.ArrayList;
   4
   5 import org.simantics.scl.compiler.common.datatypes.Constructor;
   6 import org.simantics.scl.compiler.constants.IntegerConstant;
   7 import org.simantics.scl.compiler.constants.StringConstant;
   8 import org.simantics.scl.compiler.elaboration.errors.NotPatternException;
   9 import org.simantics.scl.compiler.elaboration.expressions.EApply;
  10 import org.simantics.scl.compiler.elaboration.expressions.ELiteral;
  11 import org.simantics.scl.compiler.elaboration.expressions.EVar;
  12 import org.simantics.scl.compiler.elaboration.expressions.Expression;
  13 import org.simantics.scl.compiler.elaboration.modules.TypeConstructor;
  14 import org.simantics.scl.compiler.environment.AmbiguousNameException;
  15 import org.simantics.scl.compiler.environment.Environment;
  16 import org.simantics.scl.compiler.environment.Environments;
  17 import org.simantics.scl.compiler.errors.ErrorLog;
  18 import org.simantics.scl.compiler.internal.parsing.declarations.DDerivingInstanceAst;
  19 import org.simantics.scl.compiler.internal.parsing.declarations.DInstanceAst;
  20 import org.simantics.scl.compiler.internal.parsing.declarations.DValueAst;
  21 import org.simantics.scl.compiler.internal.parsing.expressions.Expressions;
  22 import org.simantics.scl.compiler.internal.parsing.translation.ProcessedDInstanceAst;
  23 import org.simantics.scl.compiler.internal.parsing.translation.ValueRepository;
  24 import org.simantics.scl.compiler.internal.parsing.types.TVarAst;
  25 import org.simantics.scl.compiler.types.TCon;
  26
  27 class ShowDeriver implements InstanceDeriver {
  28
  29     private static final IntegerConstant CONST_10 = new IntegerConstant(10);
  30
  31     @Override
  32     public void derive(
  33             ErrorLog errorLog,
  34             Environment environment,
  35             ArrayList<ProcessedDInstanceAst> instancesAst,
  36             DDerivingInstanceAst der) {
  37      // Analyze
  38         if(der.types.length != 1) {
  39             errorLog.log(der.location, "Invalid number of parameters to " + der.name);
  40             return;
  41         }
  42         TVarAst headType = DerivingUtils.getHeadType(der.types[0]);
  43         if(headType == null) {
  44             errorLog.log(der.types[0].location, "Cannot derive Show instance for the type " + headType + ".");
  45             return;
  46         }
  47         TCon con;
  48         try {
  49             con = Environments.getTypeConstructorName(environment, headType.name);
  50         } catch (AmbiguousNameException e1) {
  51             errorLog.log(headType.location, e1.getMessage());
  52             return;
  53         }
  54         if(con == null) {
  55             errorLog.log(headType.location, "Couldn't resolve " + headType.name);
  56             return;
  57         }
  58         TypeConstructor tcon = environment.getTypeConstructor(con);
  59         if(tcon == null) {
  60             errorLog.log(headType.location, "Didn't find type constructor for " + headType.name);
  61             return;
  62         }
  63         if(tcon.isOpen) {
  64             errorLog.log(headType.location, "Cannot derive instance for open data types.");
  65             return;
  66         }
  67
  68         // Generate
  69         DInstanceAst instanceAst = new DInstanceAst(der.location, der.context, der.name, der.types);
  70         ValueRepository valueDefs = new ValueRepository();
  71         for(Constructor constructor : tcon.constructors) {
  72             int l = constructor.parameterTypes.length;
  73             String[] par = new String[l];
  74             for(int i=0;i<l;++i) {
  75                 par[i] = "v" + i;
  76             }
  77             Expression lhs = new EApply(
  78                     new EVar("<+"),
  79                     new EVar("sb"),
  80                     new EApply(new EVar(constructor.name.name), Expressions.vars(par))
  81                     );
  82             Expression value;
  83             value = new EApply(new EVar("<<"), new EVar("sb"),
  84                     new ELiteral(new StringConstant(constructor.name.name)));
  85             for(int i=0;i<l;++i) {
  86                 value = new EApply(new EVar("<<"),
  87                         value,
  88                         new ELiteral(new StringConstant(" "))
  89                         );
  90                 value = new EApply(new EVar("<+"),
  91                         value,
  92                         new EApply(new EVar("Par"), new ELiteral(CONST_10), new EVar("v" + i))
  93                         );
  94             }
  95
  96             try {
  97                 DValueAst valueAst = new DValueAst(lhs, value);
  98                 valueAst.setLocationDeep(der.location);
  99                 valueDefs.add(valueAst);
 100                 /*valueDefs.addAnnotation("<+", new DAnnotationAst(new EVar("@private"),
 101                         Collections.<Expression>emptyList()));*/
 102             } catch (NotPatternException e) {
 103                 errorLog.log(e.getExpression().location, "Not a pattern.");
 104             }
 105         }
 106         instancesAst.add(new ProcessedDInstanceAst(instanceAst, valueDefs));
 107     }
 108
 109 }