Re: [racket-users] Apparent Datalog error?

2018-01-31 Thread George Neuner
On 1/31/2018 2:51 PM, Matthias Felleisen wrote: > On Jan 31, 2018, at 2:15 PM, George Neuner wrote: > > > On 1/31/2018 2:10 PM, Sam Caldwell wrote: >> Your definition of `ancestor` is one or two steps of parentage: >> >> > ancestor(A, B) :- parent(A, B). >> >

Re: [racket-users] Apparent Datalog error?

2018-01-31 Thread Matthias Felleisen
> On Jan 31, 2018, at 2:15 PM, George Neuner wrote: > > > On 1/31/2018 2:10 PM, Sam Caldwell wrote: >> Your definition of `ancestor` is one or two steps of parentage: >> >> > ancestor(A, B) :- parent(A, B). >> > ancestor(A, B) :- >> parent(A, C), >> parent(C,

Re: [racket-users] Apparent Datalog error?

2018-01-31 Thread George Neuner
On 1/31/2018 2:10 PM, Sam Caldwell wrote: Your definition of `ancestor` is one or two steps of parentage: > ancestor(A, B) :- parent(A, B). > ancestor(A, B) :-   parent(A, C),   parent(C, B). I suspect you want one of those lines to appeal to the `ancestor` relation to allow longer

Re: [racket-users] Apparent Datalog error?

2018-01-31 Thread Sam Caldwell
Your definition of `ancestor` is one or two steps of parentage: > ancestor(A, B) :- parent(A, B). > ancestor(A, B) :- parent(A, C), parent(C, B). I suspect you want one of those lines to appeal to the `ancestor` relation to allow longer chains. - Sam Caldwell On Wed, Jan 31, 2018 at 1:53 PM,