public LexicalStateMachine()
{
CurrentState = LexicalMachineState.EMPTY;
transitions = new Dictionary <LexicalStateTransition, LexicalMachineState>
{
{ new LexicalStateTransition(LexicalMachineState.EMPTY, AtomType.DIGIT), LexicalMachineState.INT_TOKEN },
{ new LexicalStateTransition(LexicalMachineState.EMPTY, AtomType.LETTER), LexicalMachineState.VAR_TOKEN },
{ new LexicalStateTransition(LexicalMachineState.EMPTY, AtomType.QUOTE), LexicalMachineState.QUOTED_STRING_TOKEN },
{ new LexicalStateTransition(LexicalMachineState.EMPTY, AtomType.SPECIAL), LexicalMachineState.SPECIAL_TOKEN },
{ new LexicalStateTransition(LexicalMachineState.EMPTY, AtomType.OPENING_PAR), LexicalMachineState.SPECIAL_TOKEN },
{ new LexicalStateTransition(LexicalMachineState.EMPTY, AtomType.CLOSING_PAR), LexicalMachineState.SPECIAL_TOKEN },
{ new LexicalStateTransition(LexicalMachineState.EMPTY, AtomType.DELIMITER), LexicalMachineState.EMPTY },
{ new LexicalStateTransition(LexicalMachineState.EMPTY, AtomType.CONTROL), LexicalMachineState.EMPTY },
{ new LexicalStateTransition(LexicalMachineState.VAR_TOKEN, AtomType.DIGIT), LexicalMachineState.EMPTY },
{ new LexicalStateTransition(LexicalMachineState.VAR_TOKEN, AtomType.DELIMITER), LexicalMachineState.EMPTY },
{ new LexicalStateTransition(LexicalMachineState.VAR_TOKEN, AtomType.LETTER), LexicalMachineState.STRING_TOKEN },
{ new LexicalStateTransition(LexicalMachineState.VAR_TOKEN, AtomType.OPENING_PAR), LexicalMachineState.ARRAY_TOKEN },
{ new LexicalStateTransition(LexicalMachineState.VAR_TOKEN, AtomType.SPECIAL), LexicalMachineState.SPECIAL_TOKEN },
{ new LexicalStateTransition(LexicalMachineState.VAR_TOKEN, AtomType.CONTROL), LexicalMachineState.EMPTY },
{ new LexicalStateTransition(LexicalMachineState.INT_TOKEN, AtomType.DIGIT), LexicalMachineState.INT_TOKEN },
{ new LexicalStateTransition(LexicalMachineState.INT_TOKEN, AtomType.SPECIAL), LexicalMachineState.SPECIAL_TOKEN },
{ new LexicalStateTransition(LexicalMachineState.INT_TOKEN, AtomType.OPENING_PAR), LexicalMachineState.SPECIAL_TOKEN },
{ new LexicalStateTransition(LexicalMachineState.INT_TOKEN, AtomType.CLOSING_PAR), LexicalMachineState.SPECIAL_TOKEN },
{ new LexicalStateTransition(LexicalMachineState.INT_TOKEN, AtomType.DELIMITER), LexicalMachineState.EMPTY },
{ new LexicalStateTransition(LexicalMachineState.INT_TOKEN, AtomType.CONTROL), LexicalMachineState.EMPTY },
{ new LexicalStateTransition(LexicalMachineState.STRING_TOKEN, AtomType.LETTER), LexicalMachineState.STRING_TOKEN },
{ new LexicalStateTransition(LexicalMachineState.STRING_TOKEN, AtomType.DIGIT), LexicalMachineState.STRING_TOKEN },
{ new LexicalStateTransition(LexicalMachineState.STRING_TOKEN, AtomType.QUOTE), LexicalMachineState.STRING_TOKEN },
{ new LexicalStateTransition(LexicalMachineState.STRING_TOKEN, AtomType.OPENING_PAR), LexicalMachineState.ARRAY_TOKEN },
{ new LexicalStateTransition(LexicalMachineState.STRING_TOKEN, AtomType.SPECIAL), LexicalMachineState.SPECIAL_TOKEN },
{ new LexicalStateTransition(LexicalMachineState.STRING_TOKEN, AtomType.CONTROL), LexicalMachineState.EMPTY },
{ new LexicalStateTransition(LexicalMachineState.STRING_TOKEN, AtomType.DELIMITER), LexicalMachineState.EMPTY },
{ new LexicalStateTransition(LexicalMachineState.QUOTED_STRING_TOKEN, AtomType.DIGIT), LexicalMachineState.QUOTED_STRING_TOKEN },
{ new LexicalStateTransition(LexicalMachineState.QUOTED_STRING_TOKEN, AtomType.LETTER), LexicalMachineState.QUOTED_STRING_TOKEN },
{ new LexicalStateTransition(LexicalMachineState.QUOTED_STRING_TOKEN, AtomType.DELIMITER), LexicalMachineState.QUOTED_STRING_TOKEN },
{ new LexicalStateTransition(LexicalMachineState.QUOTED_STRING_TOKEN, AtomType.SPECIAL), LexicalMachineState.QUOTED_STRING_TOKEN },
{ new LexicalStateTransition(LexicalMachineState.QUOTED_STRING_TOKEN, AtomType.QUOTE), LexicalMachineState.EMPTY },
{ new LexicalStateTransition(LexicalMachineState.SPECIAL_TOKEN, AtomType.LETTER), LexicalMachineState.STRING_TOKEN },
{ new LexicalStateTransition(LexicalMachineState.SPECIAL_TOKEN, AtomType.DIGIT), LexicalMachineState.INT_TOKEN },
{ new LexicalStateTransition(LexicalMachineState.SPECIAL_TOKEN, AtomType.SPECIAL), LexicalMachineState.SPECIAL_TOKEN },
{ new LexicalStateTransition(LexicalMachineState.SPECIAL_TOKEN, AtomType.OPENING_PAR), LexicalMachineState.SPECIAL_TOKEN },
{ new LexicalStateTransition(LexicalMachineState.SPECIAL_TOKEN, AtomType.CLOSING_PAR), LexicalMachineState.SPECIAL_TOKEN },
{ new LexicalStateTransition(LexicalMachineState.SPECIAL_TOKEN, AtomType.DELIMITER), LexicalMachineState.EMPTY },
{ new LexicalStateTransition(LexicalMachineState.SPECIAL_TOKEN, AtomType.CONTROL), LexicalMachineState.EMPTY },
{ new LexicalStateTransition(LexicalMachineState.ARRAY_TOKEN, AtomType.DIGIT), LexicalMachineState.INDEX_OF_ARRAY_TOKEN },
{ new LexicalStateTransition(LexicalMachineState.INDEX_OF_ARRAY_TOKEN, AtomType.DIGIT), LexicalMachineState.INDEX_OF_ARRAY_TOKEN },
{ new LexicalStateTransition(LexicalMachineState.INDEX_OF_ARRAY_TOKEN, AtomType.CLOSING_PAR), LexicalMachineState.EMPTY },
{ new LexicalStateTransition(LexicalMachineState.INDEX_OF_ARRAY_TOKEN, AtomType.CONTROL), LexicalMachineState.EMPTY },
};
}
public void MoveNext(AsciiAtom command)
{
LexicalMachineState nextState = GetNext(command.Category);
if (nextState == LexicalMachineState.ARRAY_TOKEN && this.CurrentState == LexicalMachineState.VAR_TOKEN)
{
this.arrayToken = this.currentToken;
this.ClearToken();
this.CurrentState = nextState;
return;
}
else if (this.CurrentState == LexicalMachineState.INDEX_OF_ARRAY_TOKEN && command.Category != AtomType.DIGIT)
{
this.indexOrSize = int.Parse(this.currentToken);
this.ClearToken();
this.OnTokenIdentified(command);
this.CurrentState = nextState;
return;
}
else if (nextState == LexicalMachineState.VAR_TOKEN && this.CurrentState == LexicalMachineState.EMPTY)
{
this.UpdateTokenState(command);
this.CurrentState = nextState;
return;
}
else if (nextState == LexicalMachineState.EMPTY && this.CurrentState == LexicalMachineState.VAR_TOKEN ||
nextState == LexicalMachineState.EMPTY && this.CurrentState == LexicalMachineState.QUOTED_STRING_TOKEN)
{
this.UpdateTokenState(command);
this.OnTokenIdentified(command);
this.ClearToken();
this.CurrentState = nextState;
return;
}
else if (nextState == LexicalMachineState.EMPTY && command.Category == AtomType.CONTROL ||
nextState == LexicalMachineState.EMPTY && this.CurrentState != LexicalMachineState.EMPTY ||
nextState == LexicalMachineState.SPECIAL_TOKEN &&
(this.CurrentState == LexicalMachineState.STRING_TOKEN || this.CurrentState == LexicalMachineState.INT_TOKEN || this.CurrentState == LexicalMachineState.SPECIAL_TOKEN) ||
this.CurrentState == LexicalMachineState.SPECIAL_TOKEN &&
(nextState == LexicalMachineState.INT_TOKEN || nextState == LexicalMachineState.STRING_TOKEN))
{
this.OnTokenIdentified(command);
this.ClearToken();
}
this.UpdateTokenState(command);
this.CurrentState = nextState;
}
public LexicalMachineState GetNext(AtomType command)
{
LexicalMachineState nextState = this.CurrentState;
LexicalStateTransition transition = new LexicalStateTransition(CurrentState, command);
if (!transitions.TryGetValue(transition, out nextState))
{
throw new Exception("Lexical: Invalid transition: " + CurrentState + " -> " + command);
}
Console.WriteLine("Lexical :" + this.CurrentState + " -> " + nextState + " : " + command.ToString());
return(nextState);
}
public Token(LexicalMachineState state, string tokenString, AsciiAtom command)
{
this.Text = tokenString;
if (state == LexicalMachineState.STRING_TOKEN)
{
this.Type = this.Text.ToUpper() switch
{
"PRINT" => TokenType.PRINT,
"DIM" => TokenType.DIM,
"LET" => TokenType.LET,
"READ" => TokenType.READ,
"DATA" => TokenType.DATA,
"FOR" => TokenType.FOR,
"TO" => TokenType.TO,
"NEXT" => TokenType.NEXT,
"GO" => TokenType.GO,
"GOTO" => TokenType.GOTO,
"GOSUB" => TokenType.GOSUB,
"RETURN" => TokenType.RETURN,
"REM" => TokenType.REMARK,
"IF" => TokenType.IF,
"STEP" => TokenType.STEP,
"THEN" => TokenType.THEN,
"END" => TokenType.FINAL,
_ => TokenType.STRING
};
}
else if (state == LexicalMachineState.INT_TOKEN)
{
this.Type = TokenType.INT;
}
else if (state == LexicalMachineState.SPECIAL_TOKEN)
{
this.Type = this.Text switch
{
"=" => TokenType.EQUALS,
":=" => TokenType.EQUALS,
">" => TokenType.GREATER,
">=" => TokenType.GREATER_OR_EQUAL,
"<" => TokenType.LESS,
"<=" => TokenType.LESS_OR_EQUAL,
"<>" => TokenType.NOT_EQUAL,
"(" => TokenType.OPENING_BRACES,
")" => TokenType.CLOSING_BRACES,
"," => TokenType.COMMA,
"+" => TokenType.PLUS,
"-" => TokenType.MINUS,
"*" => TokenType.MULT,
"/" => TokenType.DIV,
_ => TokenType.ERROR
};
}
else if (state == LexicalMachineState.VAR_TOKEN)
{
this.Type = TokenType.VAR;
}
else if (state == LexicalMachineState.QUOTED_STRING_TOKEN)
{
this.Type = TokenType.QUOTED_STRING;
}
else if (command.Category == AtomType.CONTROL)
{
this.Type = TokenType.END;
}
else
{
this.Type = TokenType.ERROR;
}
}
public LexicalStateTransition(LexicalMachineState currentState, AtomType command)
{
this.CurrentState = currentState;
this.Command = command;
}