[Haskell-beginners] Operator orders affect parse result

[m00nlight]

 Dear Haskellers,

I have tried the "while language parser" tutorial on haskellwiki, but I encounter an problem I can not understand here,
The following is the code:

http://pastebin.com/saC9vwCn


The problem is, with the code, the parse result of "fact := a / b * c" is
*Main> parseString "fact := a / b * c"
Assign "fact" (ABinary Multiply (ABinary Divide (Var "a") (Var "b")) (Var "c"))
*Main>

But if I swap the order of "/" and "*" operators in aOperators(make "*" appear before "/" operator),  then the result is
*Main> parseString "fact := a / b * c"
Assign "fact" (ABinary Divide (Var "a") (ABinary Multiply (Var "b") (Var "c")))
*Main>

So it seems that the order of the operator will affect the parse result. What's the problem with my code?  How can I
make my program to produce consistent parse result.

Best Regards,



--m00nlight


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