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["Kok Wei Shiung" <kwshiung AT yoyo.monash.edu.my>]

Hi maude-help,

     I've encountered problem on this piece of code:

fmod CALC is 
        protecting MACHINE-INT .
        
        sorts first second answer .
        subsorts first < second < answer < MachineInt .

        op _ : MachineInt : -> first [assoc] . 
        op _*_ : MachineInt MachineInt : -> first [assoc] .
        op _/_ : MachineInt MachineInt : -> first [assoc] .
        op _+_ : first first : -> second [assoc] .
        op _-_ : first first : -> second [assoc] .
        op calc : second -> MachineInt .
        
        var N1 : MachineInt .
        var N2 : MachineInt .

        eq calc( N1 ) = N1 .
        ceq calc( N1 + N2 ) = N1 + N2 .
        ceq calc( N1 - N2 ) = N1 - N2 .
        eq calc( N1 * N2 ) = N1 * N2 .
        eq calc( N1 / N2 ) = N1 / N2 .
end fmod)

This is a simple calculator program. It suppose to take an equation, evaluate 
the (*/) first then follow by (+-). An Error message 'no loop state' appear 
when i load it into maude. Is this error caused by the grammar itself or 
syntax error of the code? How to fix this problem?


Thank you!


from,
Vincent
 

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