private void ParseArgument(MapLexer lexer, MapParserContext context, MappedDataExpression expression)
{
// We should have an identifier...
// TODO - literals
var ident = CompoundIdentifier.Parse(lexer);
// The identifier is either an attribute or a model...
if (ident.HasPrefix)
{
expression.Arguments.Add(new MappedDataArgument(context.Resolve(ident)));
}
else
{
// A model...look it up and add it...
var modelId = ident.Parts.First();
var model = context.Models.FirstOrDefault(x => x.Id == modelId);
if (model == null)
{
throw new ParserException(ident, $"Model '{modelId}' not found.");
}
expression.Arguments.Add(new MappedDataArgument(model));
}
}
private void ParseIgnore(MapParserContext context, MapLexer lexer)
{
lexer.Consume(TokenKind.Keyword, "ignore");
lexer.Consume(TokenKind.LeftCurly);
while (lexer.Token.Kind == TokenKind.Identifier || lexer.Token.Kind == TokenKind.Keyword)
{
var ignoredId = CompoundIdentifier.Parse(lexer);
var ignoredAttribute = context.Resolve(ignoredId);
context.MapList.AddIgnored(ignoredAttribute);
lexer.Consume(TokenKind.Semicolon);
}
lexer.Consume(TokenKind.RightCurly);
}
public MappedDataExpression Parse(MapLexer lexer, MapParserContext context)
{
var expression = new MappedDataExpression();
// Regardless, we should always start with an identifier. This means that functions
// are not keywords.
lexer.VerifyToken(TokenKind.Identifier);
// If the identifier is a function name, parse a function call...
if (functions.Contains(lexer.Token.Text))
{
ParseFunctionCall(lexer, context, expression);
}
else
{
// We don't have a function call, it must be an identifier. Parse it...
var ident = CompoundIdentifier.Parse(lexer);
var resolved = context.Resolve(ident);
expression.Arguments.Add(new MappedDataArgument(resolved));
}
return(expression);
}
private void ParseStatement(MapParserContext context, MapLexer lexer)
{
// Constructs:
// examples ...
// ignore ...
// with ...
// { statements }
if (lexer.Token.Kind == TokenKind.Keyword)
{
if (lexer.Token.Text == "with")
{
ParseWith(context, lexer);
return;
}
else if (lexer.Token.Text == "name")
{
ParseName(context, lexer);
return;
}
else if (lexer.Token.Text == "examples")
{
ParseExamples(context, lexer);
return;
}
else if (lexer.Token.Text == "ignore")
{
ParseIgnore(context, lexer);
return;
}
else
{
throw new ParserException($"Unexpected keyword '{lexer.Token.Text}'.", lexer.Token);
}
}
else if (lexer.Token.Kind == TokenKind.LeftCurly)
{
lexer.Consume(TokenKind.LeftCurly);
while (lexer.Token.Kind != TokenKind.RightCurly)
{
ParseStatement(context, lexer);
}
lexer.Consume(TokenKind.RightCurly);
return;
}
// Constructs:
// ident = model(ident);
// ident:ident = ident:ident;
var lhs = CompoundIdentifier.Parse(lexer);
lexer.Consume(TokenKind.Equals);
var rhs = expressionParser.Parse(lexer, context);
// A little special handling for the model function
if (rhs.FunctionName == "model")
{
var model = rhs.Arguments.First().Model;
if (model == null)
{
throw new ParserException("The 'model' function requires a model argument.");
}
context.AddModelAlias(lhs.Parts.First(), model);
lexer.Consume(TokenKind.Semicolon);
}
else
{
var target = context.Resolve(lhs);
var mapCount = context.MapList.Maps.Where(x => x.TargetAttribute.Equals(target)).Count();
var mapping = new ExpressiveMapping(IdNames.Substring(mapCount, 1), target, rhs);
context.MapList.Maps.Add(mapping);
if (lexer.Token.Kind == TokenKind.LeftCurly)
{
ParseMappingExtras(context, lexer, mapping);
}
else
{
lexer.Consume(TokenKind.Semicolon);
}
}
}