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[Ajay S Tirumala <tirumala AT uiuc.edu>]

The following is taken from Prof.Rosu's 322 notes... I think if I just 
load the following modules 


-- start --

fmod NAME-SYNTAX is protecting QID .
 sort Name .
 subsort Qid < Name .
 ops q w e r t y u i o p a s d f g h j k l z x c v b n m : -> Name .
endfm

fmod EXP-SYNTAX is protecting NAME-SYNTAX .
 protecting INT .
 sort Exp .
 subsorts Int Name < Exp .
 op _+_ : Exp Exp -> Exp [ditto] .
 op _-_ : Exp Exp -> Exp [ditto] .
 op _*_ : Exp Exp -> Exp [ditto] .
 op _/_ : Exp Exp -> Exp [prec 31] .
endfm

fmod GENERIC-STMT-SYNTAX is
 sort Stmt .
 op skip : -> Stmt .
endfm

fmod ASSIGNMENT-SYNTAX is extending GENERIC-STMT-SYNTAX .
 protecting EXP-SYNTAX .
 op _=_ : Name Exp -> Stmt [prec 33].
endfm

-- end --

The following execution is correct

Maude> parse a = b + c . 
Stmt: a = b + c

While this should return an error 

Maude> parse a + c = b .
[Stmt]: (a + c) = b 

Why is (a + c) being converted to a Name type? 

Thanks,
Ajay.