functionDeclaration method
Implementation
AstNode functionDeclaration() {
Token name = consume(TokenType.identifier, "Expect function name.");
consume(TokenType.leftParen, "Expect '(' after function name.");
final parameters = _parseParameterTokens();
consume(TokenType.leftBrace, "Expect '{' before function body.");
final body = block();
return FunctionDeclaration(name, parameters, body);
}