private void parseField(MagpieParser parser, boolean isMutable, Map<String, Field> fields) {
String name = parser.consume(TokenType.NAME).getString();
// Parse the pattern if there is one.
Pattern pattern;
if (parser.lookAhead(TokenType.EQUALS) || parser.lookAhead(TokenType.LINE)) {
pattern = Pattern.wildcard();
} else {
pattern = PatternParser.parse(parser);
}
// Parse the initializer if there is one.
Expr initializer;
if (parser.match(TokenType.EQUALS)) {
initializer = parser.parseExpressionOrBlock();
} else {
initializer = null;
}
fields.put(name, new Field(isMutable, initializer, pattern));
}
@Override
public Expr parse(MagpieParser parser, Token token) {
PositionSpan span = parser.span();
String name = parser.consume(TokenType.NAME).getString();
// Parse the parents, if any.
List<String> parents = new ArrayList<String>();
if (parser.match("is")) {
do {
parents.add(parser.consume(TokenType.NAME).getString());
} while (parser.match(TokenType.COMMA));
}
parser.consume(TokenType.LINE);
// Parse the doc comment if given.
String doc = "";
if (parser.match(TokenType.DOC_COMMENT, TokenType.LINE)) {
doc = parser.last(2).getString();
}
Map<String, Field> fields = new HashMap<String, Field>();
// Parse the body.
while (!parser.match("end")) {
if (parser.match("var")) parseField(parser, true, fields);
else if (parser.match("val")) parseField(parser, false, fields);
parser.consume(TokenType.LINE);
}
return Expr.class_(span.end(), doc, name, parents, fields);
}