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));
}
