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mod text;
pub use self::text::{trim_newline, IntoTextIterator, Text, TextIterator, TextSlice};
mod interval;
pub use self::interval::{Interval, IntervalError};
#[derive(Debug, Clone, Copy)]
pub enum Strand {
Forward,
Reverse,
Unknown,
}
impl PartialEq for Strand {
fn eq(&self, other: &Strand) -> bool {
match (self, other) {
(&Strand::Forward, &Strand::Forward) => true,
(&Strand::Reverse, &Strand::Reverse) => true,
_ => false,
}
}
}
impl Strand {
pub fn from_char(strand_char: &char) -> Result<Strand, StrandError> {
match *strand_char {
'+' | 'f' | 'F' => Ok(Strand::Forward),
'-' | 'r' | 'R' => Ok(Strand::Reverse),
'.' | '?' => Ok(Strand::Unknown),
invalid => Err(StrandError::InvalidChar(invalid)),
}
}
pub fn is_unknown(&self) -> bool {
if let Strand::Unknown = *self {
true
} else {
false
}
}
}
quick_error! {
#[derive(Debug)]
pub enum StrandError {
InvalidChar(invalid_char: char) {
description("invalid character for strand conversion")
display("character {:?} can not be converted to a Strand", invalid_char)
}
}
}
pub fn scan<T: Copy, F: Fn(T, T) -> T>(a: &mut [T], op: F) {
let mut s = a[0];
for v in a.iter_mut().skip(1) {
s = op(s, *v);
*v = s;
}
}
pub fn prescan<T: Copy, F: Fn(T, T) -> T>(a: &mut [T], neutral: T, op: F) {
let mut s = neutral;
for v in a.iter_mut() {
let t = *v;
*v = s;
s = op(s, t);
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test_scan() {
let mut a = vec![1, 0, 0, 1];
scan(&mut a[..], |a, b| a + b);
assert_eq!(a, vec![1, 1, 1, 2]);
}
#[test]
fn test_prescan() {
let mut a = vec![1, 0, 0, 1];
prescan(&mut a[..], 0, |a, b| a + b);
assert_eq!(a, vec![0, 1, 1, 1]);
}
#[test]
fn test_strand() {
assert_eq!(Strand::from_char(&'+').unwrap(), Strand::Forward);
assert_eq!(Strand::from_char(&'-').unwrap(), Strand::Reverse);
assert!(Strand::from_char(&'.').unwrap().is_unknown());
assert!(Strand::from_char(&'o').is_err());
}
}