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我已经写了河内问题的塔的TLA +规格:如何公式转换为TLA +代码
TEX
ASCII
------------------------------- MODULE Hanoi -------------------------------
EXTENDS Sequences, Integers
VARIABLE A, B, C
CanMove(x,y) == /\ Len(x) > 0
/\ IF Len(y) > 0 THEN Head(y) > Head(x) ELSE TRUE
Move(x,y,z) == /\ CanMove(x,y)
/\ x' = Tail(x)
/\ y' = <<Head(x)>> \o y
/\ z' = z
Invariant == C /= <<1,2,3>> \* When we win!
Init == /\ A = <<1,2,3>>
/\ B = <<>>
/\ C = <<>>
Next == \/ Move(A,B,C) \* Move A to B
\/ Move(A,C,B) \* Move A to C
\/ Move(B,A,C) \* Move B to A
\/ Move(B,C,A) \* Move B to C
\/ Move(C,A,B) \* Move C to A
\/ Move(C,B,A) \* Move C to B
=============================================================================
当我指定0123时,TLA模型检查器将为我解决难题公式作为不变量。
虽然我想尽量减少冗余,理想情况下我不想将未更改的变量传递给Move()
,但我无法弄清楚。我想要做的是写
Move(x,y) == /\ CanMove(x,y)
/\ x' = Tail(x)
/\ y' = <<Head(x)>> \o y
/\ UNCHANGED (Difference of and {A,B,C} and {y,x})
我怎样才能表达在TLA语言?