// expand an OR symbol throughout a rule
// error if more than one in pattern
IList <AtomicRule> ExpandSymbolMulti(AtomicRule oldrule, ObjectSymbol oldsym)
{
var pcells = oldrule.Patterns.SelectMany(p => p.Cells
.SelectMany(c => c.Where(a => a.Symbol == oldsym && !a.IsNegated)));
if (pcells.Count() != 1)
{
return(null);
}
// expand one rule per object id
var newrules = new List <AtomicRule>();
foreach (var newobj in oldsym.ObjectIds)
{
var newrule = oldrule.Clone();
for (var riter = new RuleIterator {
Rule = oldrule
}; !riter.Done; riter.Step())
{
newrule.Patterns[riter.SubRuleIndex].Cells[riter.CellIndex] = ReplaceObject(riter.PatternAtoms, oldsym, newobj);
newrule.Actions[riter.SubRuleIndex].Cells[riter.CellIndex] = ReplaceObject(riter.ActionAtoms, oldsym, newobj);
}
newrules.AddRange(ExpandRule(newrule));
}
return(newrules);
}
// expand an ambiguous direction throughout a rule
// error if more than one in pattern
IList <AtomicRule> ExpandDirectionMulti(AtomicRule oldrule, Direction olddir)
{
var pcells = oldrule.Patterns.SelectMany(p => p.Cells
.SelectMany(c => c.Where(a => a.Direction == olddir)));
if (pcells.Count() != 1)
{
_parser.CompileError("'{0}' in action cannot be matched", olddir);
}
// expand one rule per single direction
var newrules = new List <AtomicRule>();
foreach (var newdir in _expanddirlookup[olddir])
{
var newrule = oldrule.Clone();
for (var riter = new RuleIterator {
Rule = oldrule
}; !riter.Done; riter.Step())
{
newrule.Patterns[riter.SubRuleIndex].Cells[riter.CellIndex] = ReplaceDirection(riter.PatternAtoms, olddir, newdir);
newrule.Actions[riter.SubRuleIndex].Cells[riter.CellIndex] = ReplaceDirection(riter.ActionAtoms, olddir, newdir);
}
newrules.AddRange(ExpandRule(newrule));
}
return(newrules);
}
// Convert every relative direction into absolute
AtomicRule MakeAbsolute(AtomicRule rule, Direction ruledir)
{
var newrule = rule.Clone();
newrule.Directions = new HashSet <Direction>()
{
ruledir
};
MakeAbsolute(newrule.Patterns, ruledir);
if (newrule.HasAction)
{
MakeAbsolute(newrule.Actions, ruledir);
}
return(newrule);
}