ascent 0.8.0

Logic programming in Rust
Documentation 
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//! Aggregate `agg` clause

use ascent::aggregators::{count, max, mean, min, sum};
use ascent::ascent;

ascent! {
    // Facts:

    relation number(i32);

    // Rules:

    relation lowest(i32);

    lowest(y) <-- agg y = min(x) in number(x);

    relation greatest(i32);

    greatest(y) <-- agg y = max(x) in number(x);

    relation average(i32);

    average(y.round() as i32) <-- agg y = mean(x) in number(x);

    relation total(i32);

    total(y) <-- agg y = sum(x) in number(x);

    relation cardinality(usize);

    cardinality(y) <-- agg y = count() in number(_);
}

fn main() {
   let mut prog = AscentProgram::default();

   prog.number = (1..=5).map(|n| (n,)).collect();

   prog.run();

   let AscentProgram { lowest, greatest, average, total, cardinality, .. } = prog;

   assert_eq!(lowest, vec![(1,)]);
   assert_eq!(greatest, vec![(5,)]);
   assert_eq!(average, vec![(3,)]);
   assert_eq!(total, vec![(15,)]);
   assert_eq!(cardinality, vec![(5,)]);
}