Введение в синтаксис и семантику языка программирования Тьюрингол. TuringMachineEmulator: https://dl.dropboxusercontent.com/u/44802378/TuringMachine.zip

1. Смирнов Андрей
mail@ansmirnov.ru
Язык программирования Тьюрингол

2. Машина Тьюринга

3. Машина Тьюринга

4. Машина Тьюринга инкрементирующая
двоичное число
Q = {0, 1, 2}
Σ = {'0', '1', '_'}
q_begin = 0
q_end = -1

5. Грамматика языка Turingol
Letter ::= a | b | c | d | e | f | g | h | i | g | k | l | m | n | o | p | q | r | s |
t | u | v | w | x | y | z
Identifier ::= Letter Letter*
Declaration ::= tape alphabet is Identifier (, Identifier)*
PrintStatement ::= print "Identifier"
MoveStatement ::= move (left | right) one square
GoStatement ::= go to Identifier
ConditionalStatement ::= if the tape symbol is Identifier
then Statement
LabeledStatement ::= Identifier : Statement
CompoundStatement ::= { ListOfStatement }
ListOfStatement ::= Statement (; Statement)*
Statement ::= (PrintStatement | MoveStatement | GoStatement
| ConditionalStatement | LabeledStatement
| CompoundStatement)?
Program ::= Declarations ; ListOfStatements

6. tape alphabet is zero, one, blank;
walk:
if the tape symbol is "blank"
then go to findzero;
move right one square;
go to walk;
findzero:
if the tape symbol is "zero"
then {print "one"; move right one square; go to writezero};
if the tape symbol is "blank"
then {print "zero"; go to findzero};
move left one sqaure;
go to findzero;
writezero:
if the tape symbol is "one"
then {print "zero"; move right one square; go to writezero}

7. Лексический анализ

8. Синтаксический анализ
print 'one'
➲ A → a;
…
➲ A → z;
➲ I → A;
➲ I → IA;
➲ S → print 'I';

10. Применение семантических правил
➲ A → a;
● text(A) = a
…
➲ A → z;
● text(A) = z
➲ I → A;
● text(I) = text(A)
➲ I → IA;
● text(I) = text(I) text(A)
➲ S → print 'I'
● define δ(start(S), s) =
(symbol(text(I)), 0,
follow(S))
for all s in Σ

11. Литература
➲ Donald E. Knuth, Semantics of Context-Free Languages,
Springer-Verlang, 1967.
➲ Donald E. Knuth, The Art of Computer Programming, I,
Addison-Wesley, 1968.