Struct SequenceWatchers

Source

pub struct SequenceWatchers<T>where
    T: Eq + Clone + Debug + Hash,
{ /* private fields */ }

Expand description

Monitors a stream of data for multiple sequences of data items.

§Examples

use seq_watcher::SequenceWatchers;

const CTRL_C: u8 = 3;
const CTRL_D: u8 = 4;

// Watch the input stream for two consecutive <CTRL-C> characters.
let watchers = SequenceWatchers::new(&[&[CTRL_C, CTRL_C], &[CTRL_C, CTRL_D]]);

for b in b'a'..=b'z' {
    assert_eq!(false, watchers.check(&b));   // Send single ASCII byte
    assert_eq!(false, watchers.check(&CTRL_C));   // Send single <Ctrl-C>
}
assert_eq!(true, watchers.check(&CTRL_C));    // Send a second <Ctrl-C>
assert_eq!(true, watchers.check(&CTRL_D));    // Send a <Ctrl-D>

Implementations§

Source §

impl<T: Eq + Clone + Debug + Hash> SequenceWatchers<T>

Source

pub fn new(sequences: &[&[T]]) -> Self

Create a new SequenceWatchers from a slice of slices of data. The data type can be anything with Eq, Debug, and Clone traits.

Internally, the SequenceWatchers structure contains a vector of SequenceWatcher structures.

§Examples

let watchers = SequenceWatchers::new(&[&['q'], &['Q']]);

assert_eq!(true, watchers.check(&'q'));
assert_eq!(true, watchers.check(&'Q'));

Source

pub fn check(&self, value: &T) -> bool

Tells the SequenceWatchers of a new input item and checks to see if a sequence has been completed. Returns true when a sequence is completed.

§Examples

let watchers = SequenceWatchers::new(&[&[false, true], &[false, true, true]]);

assert_eq!(false, watchers.check(&true));
assert_eq!(false, watchers.check(&false));
assert_eq!(true, watchers.check(&true));    // Matches first sequence
assert_eq!(true, watchers.check(&true));    // Matches second sequence

Source

pub fn add(&mut self, new_seq: &[T])

Adds a new SequenceWatcher to the SequenceWatchers. If the sequence matches a pre-existing SequenceWatcher, it does nothing.

§Examples

let mut watchers = SequenceWatchers::new(&[]);
watchers.add(&[]);  // This does nothing.
watchers.add(&[false, true]);
watchers.add(&[false, true, true]);

assert_eq!(false, watchers.check(&true));
assert_eq!(false, watchers.check(&false));
assert_eq!(true, watchers.check(&true));    // Matches first sequence
assert_eq!(true, watchers.check(&true));    // Matches second sequence

Source

pub fn remove(&mut self, seq: &[T]) -> Option<SequenceWatcher<T>>

Removes a sequence watcher for a given sequence. It returns the removed SequenceWatcher.

§Examples

let mut watchers = SequenceWatchers::new(&[&[false, true], &[false, true, true]]);
watchers.remove(&[false, true, true]);

assert_eq!(false, watchers.check(&true));
assert_eq!(false, watchers.check(&false));
assert_eq!(true, watchers.check(&true));    // Matches first sequence
assert_eq!(false, watchers.check(&true));   // Matches second sequence, which was removed

Source

pub fn len(&self) -> usize

Returns the number of sequences being monitored.

§Examples

let watchers = SequenceWatchers::new(&[&['A'], &['B'], &['C'], &['D']]);

assert_eq!(4, watchers.len());

Source

pub fn sequences(&self) -> Keys<'_, Vec<T>, SequenceWatcher<T>>

Returns an iterator over the sequences being monitored by the SequenceWatchers.

§Examples

let watchers = SequenceWatchers::new(&[&[false, true], &[false, true, true]]);

let mut sequences: Vec<&Vec<bool>> = watchers.sequences().collect();
sequences.sort();   // Make sure keys are sorted.
let mut sequences = sequences.into_iter();
assert_eq!(sequences.next(), Some(&vec![false, true]));
assert_eq!(sequences.next(), Some(&vec![false, true, true]));
assert_eq!(sequences.next(), None);