Dear Maude Abusers,

A new alpha release can be accessed at SRI-CSL in:

~eker/public_html/Maude/Alpha112b/

or downloaded from:

http://www.csl.sri.com/~eker/Maude/Alpha112b/

Alpha release site authentication:

User Name: maudeabuser
Password: bughunter

This is an urgent bug fix release.

Bug fixes
==========
(1) A bug introduced by some optimizations on AU instantiation
that I added in alpha111b. Provoked by this example from Santiago:

red in META-LEVEL :
metaVariantUnify(mod 'LIST-VENDING is
  nil
  sorts 'Bool ; 'Coin ; 'CoinList ; 'Item ; 'Items ; 'State ; 'Universal .
  subsort 'Coin < 'CoinList .
  subsort 'Item < 'Items .
  op '$ : nil -> 'Coin [none] .
  op '<_|_> : 'CoinList 'Items -> 'State [none] .
  op '_._ : 'CoinList 'CoinList -> 'CoinList [assoc] .
  op '_=/=_ : 'Universal 'Universal -> 'Bool [prec(51) poly(1 2) special(
    id-hook('EqualitySymbol, nil) 
    term-hook('equalTerm, 'false.Bool) 
    term-hook('notEqualTerm, 'true.Bool))] .
  op '_==_ : 'Universal 'Universal -> 'Bool [prec(51) poly(1 2) special(
    id-hook('EqualitySymbol, nil) 
    term-hook('equalTerm, 'true.Bool) 
    term-hook('notEqualTerm, 'false.Bool))] .
  op '__ : 'Items 'Items -> 'Items [assoc comm id('mt.Items)] .
  op '_and_ : 'Bool 'Bool -> 'Bool [assoc comm prec(55)] .
  op '_implies_ : 'Bool 'Bool -> 'Bool [prec(61) gather('e 'E)] .
  op '_or_ : 'Bool 'Bool -> 'Bool [assoc comm prec(59)] .
  op '_xor_ : 'Bool 'Bool -> 'Bool [assoc comm prec(57)] .
  op 'a : nil -> 'Item [none] .
  op 'c : nil -> 'Item [none] .
  op 'false : nil -> 'Bool [ctor special(
    id-hook('SystemFalse, nil))] .
  op 'if_then_else_fi : 'Bool 'Universal 'Universal -> 'Universal [poly(2 3 0) special(
    id-hook('BranchSymbol, nil) 
    term-hook('1, 'true.Bool) 
    term-hook('2, 'false.Bool))] .
  op 'mt : nil -> 'Items [none] .
  op 'nil : nil -> 'CoinList [none] .
  op 'not_ : 'Bool -> 'Bool [prec(53)] .
  op 'q : nil -> 'Coin [none] .
  op 'true : nil -> 'Bool [ctor special(
    id-hook('SystemTrue, nil))] .
  none
  eq '$.Coin = '_._['q.Coin,'q.Coin,'q.Coin,'q.Coin] [variant] .
  eq '_._['CL:CoinList,'nil.CoinList] = 'CL:CoinList [variant] .
  eq '_._['nil.CoinList,'CL:CoinList] = 'CL:CoinList [variant] .
  eq '_._['CL:CoinList,'nil.CoinList,'Y@@@:`[CoinList`]] = '_._['CL:CoinList,'Y@@@:`[CoinList`]] [variant] .
  eq '_._['X@@@:`[CoinList`],'CL:CoinList,'nil.CoinList] = '_._['X@@@:`[CoinList`],'CL:CoinList] [variant] .
  eq '_._['X@@@:`[CoinList`],'nil.CoinList,'CL:CoinList] = '_._['X@@@:`[CoinList`],'CL:CoinList] [variant] .
  eq '_._['nil.CoinList,'CL:CoinList,'Y@@@:`[CoinList`]] = '_._['CL:CoinList,'Y@@@:`[CoinList`]] [variant] .
  eq '_._['X@@@:`[CoinList`],'CL:CoinList,'nil.CoinList,'Y@@@:`[CoinList`]] = '_._['X@@@:`[CoinList`],'CL:CoinList,'Y@@@:`[CoinList`]] [variant] .
  eq '_._['X@@@:`[CoinList`],'nil.CoinList,'CL:CoinList,'Y@@@:`[CoinList`]] = '_._['X@@@:`[CoinList`],'CL:CoinList,'Y@@@:`[CoinList`]] [variant] .
  rl '<_|_>['_._['CL1:CoinList,'$.Coin,'CL2:CoinList],'I:Items] => '<_|_>['_._['CL1:CoinList,'CL2:CoinList],'__['c.Item,'I:Items]] [none] .
  rl '<_|_>['_._['CL1:CoinList,'q.Coin,'CL2:CoinList,'q.Coin,'CL3:CoinList,'q.Coin,'CL4:CoinList],'I:Items] => '<_|_>['_._['CL1:CoinList,'CL2:CoinList,'CL3:CoinList,'CL4:CoinList],'__['a.Item,'I:Items]] [none] .
endm, '<_|_>['_._['#1:CoinList,'_._['#2:CoinList,'_._['#3:CoinList,'#4:CoinList]]],'a.Item] =? '<_|_>['_._['#11:CoinList,'_._['$.Coin,'#12:CoinList]],'#13:Items], (empty).EmptyCommaList, 14, 143)
.

(2) A bug where the garbage collector unexpectedly runs during
the initialization of a VariantUnificationProblem object causing
memory corruption. Provoked by this example from Santiago:

mod NARROWING-VENDING-MACHINE is
  sorts Coin Item Marking Money State .
  subsort Coin < Money .
  
  op empty : -> Money .
  op __ : Money Money -> Money [assoc comm id: empty] .
  
  subsort Money Item < Marking .
  op __ : Marking Marking -> Marking [assoc comm id: empty] .
  
  op <_> : Marking -> State .
  ops $ q : -> Coin .
  ops a c : -> Item .

  var M : Marking .

  rl [narrow] : < M $ > => < M c > .
  rl [narrow] : < M $ > => < M a q > .
  eq [change] : q q q q = $ [variant] .
endm

vu-narrow [,5] < C1:Coin C2:Coin C3:Coin C4:Coin > =>! < M:Money a c > .

Steven