Dear Maude (ab-)users

A new alpha release, 

~eker/AlphaRelease62/

is available. For people on this list who don't have a CSL account
it's ftp-able from ftp.csl.sri.com in
     pub/users/eker/MaudeAbusers/alphaRelease62.tar.gz

This version has a first approximation to the Maude 2.0
syntax, semantics and metalevel.

Some Caveats:
=============
Rewrite conditions still are not implemented (though they parse).
The new rewrite semantics for unbound variables is not implemented.
The compiler does not work in this version.
meta-apply/meta-xapply/meta-match/meta-xmatch are not implemented.
specials in the meta level are not implemented (those that worked in
the old metalevel *might* work since I left this code in).
meta-pretty-print has problems with kinds.
meta-replace and meta-substitute are not implemented - but they could
easily be written in Maude.

I have made several changes to Narciso's spec for the Maude 2.0 meta
level:

(1) the sorts_. constructor is eliminated - the syntax now goes into
    the mod/fmod construtors.

(2) sortInKind and sameComponent have been replaced by the more general
    sameKind operator.

(3) completeName is lifted to types for simplicity.

(4) the metalevel is now split into 3 modules for metaterms,
    metamodules and descent functions.

I have only built a version for Linux.

Some example reductions in the new metalevel:

select META-LEVEL .

red meta-reduce(
fmod 'FOO is
  protecting 'MACHINE-INT .
  sorts none .
  none
  op 'fact : 'MachineInt -> 'MachineInt [none] .
  none
  eq 'fact['0.MachineInt] = '1.NzMachineInt .
  ceq 'fact['X:MachineInt] = '_*_['X:MachineInt, 'fact['_-_['X:MachineInt,'1.NzMachineInt]]]
      if '_>=_['X:MachineInt, '0.MachineInt] = 'true.Bool /\
	 '_<_['X:MachineInt, '20.MachineInt] = 'true.Bool .
endfm, 'fact['21.NzMachineInt]) .

red meta-reduce(
fmod 'FOO is
  protecting 'STRING .
  sorts none .
  none
  none
  none
  none
endfm, '"this is\na string".String) .

red meta-reduce(
fmod 'FOO is
  protecting 'FLOAT .
  sorts none .
  none
  none
  none
  none
endfm, '_+_['1.0.Float,'1.0.Float]) .

red completeName(
fmod 'FOO is
  protecting 'BOOL .
  sorts 'NzNat ; 'Nat ; 'NzInt .
  subsort 'NzNat < 'Nat .
  subsort 'NzNat < 'NzInt .
  none
  none
  none
endfm, '`[NzInt`]) .

red meta-rewrite(
mod 'FOO is
  nil
  sorts 'Foo .
  none
  op 'a : nil -> 'Foo [none] .
  op 'b : nil -> 'Foo [none] .
  none
  none
  rl ['c]: 'a.Foo => 'b.Foo .
  rl ['c]: 'b.Foo => 'a.Foo .
endm, 'a.Foo, 2) .

Steven