/// <summary>
/// Create and initialize a new return statement node.
/// </summary>
/// <param name="parent">The parent node that defines the statement.</param>
/// <param name="token">The up-arrow return operator.</param>
protected internal ReturnStatementNode(IStatementParentNode parent, ReturnOperatorToken token)
: base(parent)
{
#if DEBUG
if (token == null)
throw new ArgumentNullException("token");
#endif
this.Token = token;
}
protected virtual ReturnStatementNode ParseReturnStatement(IStatementParentNode parent, ReturnOperatorToken returnOperator)
{
// PARSE: <return statement> ::= returnOperator <expression>
// Also: <statements> ::= <return statement> [’.’]
ReturnStatementNode result = new ReturnStatementNode(parent, returnOperator);
Token token = this.GetNextTokenxx(Preference.NegativeSign);
ExpressionNode expression = this.ParseExpression(result, token);
if (expression == null)
this.ReportParserError(result, SemanticErrors.MissingExpression, token);
SpecialCharacterToken period = null;
token = this.GetNextTokenxx(Preference.Default);
if (Parser.IsStatementDelimiter(token))
{
period = (SpecialCharacterToken)token;
token = this.GetNextTokenxx(Preference.Default);
}
result.SetContents(expression, period);
// Returns statement ... should have reached the end of the statement.
this.ResidueToken = token;
if (token is EofToken)
return result; // OK
else if (Parser.IsBlockEndDelimiter(token))
return result; // OK;
else if (Parser.IsStatementDelimiter(token))
this.ReportParserError(result, SemanticErrors.MissingStatement, token);
else
this.ReportParserError(result, SemanticErrors.CodeAfterReturnStatement, token);
return result;
}