public static EType Parse(string densityStr)
{
if (string.IsNullOrEmpty(densityStr))
{
var res = new DensityExpressionResult <FieldType <int, PType>, int, PType> {
ErrorString = "Empty expression string!"
};
return(res);
}
try
{
var input = new AntlrInputStream(densityStr);
var lexer = new DensityExpressionGrammarLexer(input);
var tokens = new CommonTokenStream(lexer);
var parser = new DensityExpressionGrammarParser(tokens);
var ctx = parser.compileUnit();
var visitor = new DieVisitor();
var res = visitor.VisitCompileUnit(ctx);
return(res);
} catch (Exception e)
{
var res = new DensityExpressionResult <FieldType <int, PType>, int, PType> {
ErrorString = e.Message
};
return(res);
}
}
virtual public DensityExpressionResult <G, M, RF> VisitCompileUnit(DensityExpressionGrammarParser.CompileUnitContext ctx)
{
var isDensity = ctx.density() != null;
var isProbability = ctx.probability() != null;
var density = isDensity
? VisitDensity(ctx.density())
: null;
var probability = isProbability
? VisitProbability(ctx.probability())
: (RF?)null;
var errorString = (isDensity || isProbability)
? null
: "No valid Density or Probability!";
var res = new DensityExpressionResult <G, M, RF>
{
Density = density,
Probability = probability,
ErrorString = errorString
};
return(res);
}
