Re: Junction Algebra

2009-03-30 Thread Martin Kealey
On Mon, 30 Mar 2009, Mark J. Reed wrote: > >        ( $a <= any(-1,+1) <= $b ) == ( $a <= any(-1,+1) && any(-1,+1) <= $b > > ) > > Clearly, the RHS is true for $a == $b == 0, but I'm not sure the LHS > shouldn't also be. Isn't it just syntactic sugar for the RHS? I suspect not. Rather I think th

Re: Junction Algebra

2009-03-30 Thread Mark J. Reed
On Mon, Mar 30, 2009 at 9:44 PM, Martin D Kealey wrote: > This would certainly be false: > >        ( $a <= any(-1,+1) <= $b ) == ( $a <= any(-1,+1) && any(-1,+1) <= $b ) Clearly, the RHS is true for $a == $b == 0, but I'm not sure the LHS shouldn't also be. Isn't it just syntactic sugar for the

Re: Junction Algebra

2009-03-30 Thread Martin D Kealey
On Mon, 30 Mar 2009, Jon Lang wrote: > Here's another useful one: > > any($x) eqv all($x) eqv one($x) eqv $x > > but: > > none($x) !eqv $x > > That is, applying any, all, or one to a one-item list produces the > equivalent to a single item. For an empty list: any() eqv all() eqv > (). But

Re: Junction Algebra

2009-03-30 Thread Jon Lang
Here's another useful one: any($x) eqv all($x) eqv one($x) eqv $x but: none($x) !eqv $x That is, applying any, all, or one to a one-item list produces the equivalent to a single item. For an empty list: any() eqv all() eqv (). But what about one() and none()? -- Jonathan "Dataweaver

Re: Junction Algebra

2009-03-29 Thread Damian Conway
Richard Hainsworth conjectured: > 1) Is the following true for an any junction? > any( ... , any('foo','bar')) === any(...,'foo','bar') > > If yes, then > if an 'any' junction is contained in an outer 'any', the inner 'any' can be > factored out? Yes. More precisely, an 'any' that is directly nes

Re: Junction Algebra

2009-03-28 Thread Patrick R. Michaud
On Sat, Mar 28, 2009 at 10:19:31AM -0500, Patrick R. Michaud wrote: > On Sat, Mar 28, 2009 at 02:08:22PM +0300, Richard Hainsworth wrote: > > 3) Conjecture: The following is true of all junction types, eg., > > junc(..., junc(...)) === junc(..., ...) > > The conjecture is false for one/none juncti

Re: Junction Algebra

2009-03-28 Thread Patrick R. Michaud
On Sat, Mar 28, 2009 at 02:08:22PM +0300, Richard Hainsworth wrote: > 3) Conjecture: The following is true of all junction types, eg., > junc(..., junc(...)) === junc(..., ...) The conjecture is false for one/none junctions: one(0, one(1, 1)) # true one(0, 1, 1) # fal