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[Paolo Picci <paolo.picci AT gmail.com>]

hi all
how i can use Universal type?
Universal is not a real type i can't declare sometings like X:Universal .

fmod HET-LIST is
 protecting CONVERSION .
 sort List .
 op nil : -> List .
 op __ : Universal List -> List [ctor poly (1)] .
endfm

this is an example from the book of maude.
now how can use this list in the common use?
how i can write a common function like head or tail over this
function?
i need a function like find for type String so:

op find : String List -> Bool .
eq find(X:String, nil) = false .
eq find(X:String, X:String XSHL:List) = true .

but the recursive case i cant write
eq find(X:String,  X1:String XSHL:List) = find(X:String,
XSHL:List)  .

because for example the list    1 2.2 "foo" 'qid "bar"  don't match
the 3 eq