Struct Database

Source

pub struct Database { /* private fields */ }

Expand description

The main type to interact with Yéter

This structure holds caches and effects for each query type.

Implementations§

Source §

impl Database

Source

pub fn new() -> Self

Creates an empty database

Examples found in repository ?

examples/basic.rs (line 9)

8fn main() {
9    let db = yeter::Database::new();
10    let len1 = string::len(&db, "hello".into());
11    let len2 = string::len(&db, "hello".into());
12    let len3 = string::len(&db, "world".into());
13    assert_eq!(len1, len2);
14    assert_eq!(len1, len3);
15}

More examples

Hide additional examples

examples/effects.rs (line 12)

11fn main() {
12    let db = yeter::Database::new();
13    let len1 = string::len(&db, "".into());
14    for msg in db.effect::<&'static str>() {
15        println!("EFFECT [1]: {}", msg);
16    }
17    let len2 = string::len(&db, "".into());
18    for msg in db.effect::<&'static str>() {
19        println!("EFFECT [2]: {}", msg);
20    }
21    let len3 = string::len(&db, "aaaa".into());
22    for msg in db.effect::<&'static str>() {
23        println!("EFFECT [3]: {}", msg);
24    }
25    assert_eq!(len1, len2);
26    assert_eq!(*len3, 4);
27}

Source

pub fn run<'input, F, Q>(&self, f: F, i: Q::Input) -> Rc<Q::Output>
where F: Fn(&Database, Q::Input) -> Q::Output, Q: QueryDef, Q::Input: Hash + 'input, Q::Output: 'static,

Runs a query (or not if it the result is already in the cache)

Panics if a query ends up in a cyclic computation

Source

pub fn try_run<'input, F, Q>( &self, f: F, i: Q::Input, ) -> Result<Rc<Q::Output>, CycleError>
where F: Fn(&Database, Q::Input) -> Q::Output, Q: QueryDef, Q::Input: Hash + 'input, Q::Output: 'static,

Tries to runs a query (or not if it the result is already in the cache)

Source

pub fn effect<T: 'static + Clone + Send>(&self) -> Vec<T>

Returns a side effect collection

Examples found in repository ?

examples/effects.rs (line 14)

11fn main() {
12    let db = yeter::Database::new();
13    let len1 = string::len(&db, "".into());
14    for msg in db.effect::<&'static str>() {
15        println!("EFFECT [1]: {}", msg);
16    }
17    let len2 = string::len(&db, "".into());
18    for msg in db.effect::<&'static str>() {
19        println!("EFFECT [2]: {}", msg);
20    }
21    let len3 = string::len(&db, "aaaa".into());
22    for msg in db.effect::<&'static str>() {
23        println!("EFFECT [3]: {}", msg);
24    }
25    assert_eq!(len1, len2);
26    assert_eq!(*len3, 4);
27}

Source

pub fn do_effect<T: 'static + Clone + Send>(&self, eff: T)

Produces a side effect

Examples found in repository ?

examples/effects.rs (line 5)

3    pub fn len(db: &yeter::Database, input: String) -> usize {
4        if input.is_empty() {
5            db.do_effect("Empty string");
6        }
7        input.len()
8    }