lemma-engine 0.8.12

A language that means business.
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169

use lemma::parsing::ast::DateTimeValue;
use lemma::*;
use rust_decimal::Decimal;
use std::collections::HashMap;
use std::str::FromStr;

#[test]
fn test_modulo_simple() {
    let mut engine = Engine::new();
    engine
        .load(
            r#"
spec test
data a: 10
data b: 3
rule remainder: a % b
"#,
            lemma::SourceType::Labeled("test"),
        )
        .unwrap();
    let now = DateTimeValue::now();

    let response = engine
        .run("test", Some(&now), HashMap::new(), false)
        .unwrap();
    let result = response.results.get("remainder").unwrap();

    match &result.result {
        lemma::OperationResult::Value(lit) => {
            if let lemma::ValueKind::Number(n) = &lit.value {
                assert_eq!(n, &Decimal::from_str("1").unwrap())
            } else {
                panic!("Expected number, got {:?}", result.result);
            }
        }
        _ => panic!("Expected number, got {:?}", result.result),
    }
}

#[test]
fn test_power_simple() {
    let mut engine = Engine::new();
    engine
        .load(
            r#"
spec test
data base: 2
data exponent: 3
rule result: base ^ exponent
"#,
            lemma::SourceType::Labeled("test"),
        )
        .unwrap();
    let now = DateTimeValue::now();

    let response = engine
        .run("test", Some(&now), HashMap::new(), false)
        .unwrap();
    let result = response.results.get("result").unwrap();

    match &result.result {
        lemma::OperationResult::Value(lit) => {
            if let lemma::ValueKind::Number(n) = &lit.value {
                assert_eq!(n, &Decimal::from_str("8").unwrap())
            } else {
                panic!("Expected number, got {:?}", result.result);
            }
        }
        _ => panic!("Expected number, got {:?}", result.result),
    }
}

#[test]
fn test_modulo_in_expression() {
    let mut engine = Engine::new();
    engine
        .load(
            r#"
spec test
data value: 17
rule is_even: (value % 2) is 0
rule is_odd: (value % 2) is 1
"#,
            lemma::SourceType::Labeled("test"),
        )
        .unwrap();
    let now = DateTimeValue::now();

    let response = engine
        .run("test", Some(&now), HashMap::new(), false)
        .unwrap();

    let is_even = response.results.get("is_even").unwrap();
    assert_eq!(
        is_even.result,
        lemma::OperationResult::Value(Box::new(lemma::LiteralValue::from_bool(false)))
    );

    let is_odd = response.results.get("is_odd").unwrap();
    assert_eq!(
        is_odd.result,
        lemma::OperationResult::Value(Box::new(lemma::LiteralValue::from_bool(true)))
    );
}

#[test]
fn test_power_with_fractions() {
    let mut engine = Engine::new();
    engine
        .load(
            r#"
spec test
data base: 4
rule square_root: base ^ 0.5
"#,
            lemma::SourceType::Labeled("test"),
        )
        .unwrap();
    let now = DateTimeValue::now();

    let response = engine
        .run("test", Some(&now), HashMap::new(), false)
        .unwrap();
    let result = response.results.get("square_root").unwrap();

    match &result.result {
        lemma::OperationResult::Value(lit) => {
            if let lemma::ValueKind::Number(n) = &lit.value {
                assert_eq!(n, &Decimal::from_str("2").unwrap());
            } else {
                panic!("Expected number result");
            }
        }
        _ => panic!("Expected number, got {:?}", result.result),
    }
}

#[test]
fn test_combined_operations() {
    let mut engine = Engine::new();
    engine
        .load(
            r#"
spec test
data x: 10
data y: 3
rule calculation: (x % y) + (2 ^ 3)
"#,
            lemma::SourceType::Labeled("test"),
        )
        .unwrap();
    let now = DateTimeValue::now();

    let response = engine
        .run("test", Some(&now), HashMap::new(), false)
        .unwrap();
    let result = response.results.get("calculation").unwrap();

    match &result.result {
        lemma::OperationResult::Value(lit) => {
            if let lemma::ValueKind::Number(n) = &lit.value {
                assert_eq!(n, &Decimal::from_str("9").unwrap());
            } else {
                panic!("Expected number, got {:?}", result.result);
            }
        }
        _ => panic!("Expected number, got {:?}", result.result),
    }
}