public bool Parse(List<Token> tokens)
{
//check for the correct start to our mini pascal program
Tokens = tokens;
//check for 'program <name> header'
//should move this into statement probably
if (Tokens[currentToken].Type != TokenType.ProgramSym) {
WriteError("Missing 'Program' symbol", Tokens[currentToken]);
AdvanceToken();
}
//next token should be an identifier...
AdvanceToken();
if (Tokens[currentToken].Type != TokenType.Identifier) {
WriteError("Missing program identifier", Tokens[currentToken]);
}
assembler = new Assembler(Tokens[currentToken].Value);
//eat the input until semicolon
while (Tokens[currentToken].Type != TokenType.Semicolon) {
AdvanceToken();
if (currentToken >= Tokens.Count-1) {
WriteError("Expected Semicolon end of first line", Tokens[Tokens.Count-1]);
return false;
}
}
AdvanceToken();
//parse variables
if (Tokens[currentToken].Type == TokenType.VarSym) {
if (!ParseVariables()) {
WriteError("Error parsing variables", Tokens[Tokens.Count - 1]);
return false;
}
}
if (Tokens[currentToken].Type != TokenType.BeginSym) {
WriteError("Missing 'Begin' symbol", Tokens[currentToken]);
}
AdvanceToken();
Statement();
while (Tokens[currentToken].Type == TokenType.Semicolon ) {
AdvanceToken();
Statement();
}
if (Tokens[currentToken].Type != TokenType.EndSym) {
WriteError("Expected 'End' symbol", Tokens[currentToken]);
}
if (parseSuccessful) {
assembler.FinalizeCode();
}
else {
assembler.RemoveFile();
}
return parseSuccessful;
}
public bool Parse(List <Token> tokens)
{
//check for the correct start to our mini pascal program
Tokens = tokens;
//check for 'program <name> header'
//should move this into statement probably
if (Tokens[currentToken].Type != TokenType.ProgramSym)
{
WriteError("Missing 'Program' symbol", Tokens[currentToken]);
AdvanceToken();
}
//next token should be an identifier...
AdvanceToken();
if (Tokens[currentToken].Type != TokenType.Identifier)
{
WriteError("Missing program identifier", Tokens[currentToken]);
}
assembler = new Assembler(Tokens[currentToken].Value);
//eat the input until semicolon
while (Tokens[currentToken].Type != TokenType.Semicolon)
{
AdvanceToken();
if (currentToken >= Tokens.Count - 1)
{
WriteError("Expected Semicolon end of first line", Tokens[Tokens.Count - 1]);
return(false);
}
}
AdvanceToken();
//parse variables
if (Tokens[currentToken].Type == TokenType.VarSym)
{
if (!ParseVariables())
{
WriteError("Error parsing variables", Tokens[Tokens.Count - 1]);
return(false);
}
}
if (Tokens[currentToken].Type != TokenType.BeginSym)
{
WriteError("Missing 'Begin' symbol", Tokens[currentToken]);
}
AdvanceToken();
Statement();
while (Tokens[currentToken].Type == TokenType.Semicolon)
{
AdvanceToken();
Statement();
}
if (Tokens[currentToken].Type != TokenType.EndSym)
{
WriteError("Expected 'End' symbol", Tokens[currentToken]);
}
if (parseSuccessful)
{
assembler.FinalizeCode();
}
else
{
assembler.RemoveFile();
}
return(parseSuccessful);
}