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pub fn split<F: Fn(char) -> bool>(s: &str, f: F) -> (&str, &str) {
let at = find(s, f);
(&s[..at], &s[at..])
}
pub fn slice<'a>(args: impl SliceArgs<'a>) -> &'a str {
let (beg, s, end) = args.get();
&s[beg.min(s.len())..end.min(s.len())]
}
type Args<'a> = (usize, &'a str, usize);
pub trait SliceArgs<'a> {
fn get(self) -> Args<'a>;
}
impl<'a> SliceArgs<'a> for Args<'a> {
fn get(self) -> Self {
self
}
}
impl<'a> SliceArgs<'a> for (usize, &'a str) {
fn get(self) -> Args<'a> {
(self.0, self.1, self.1.len())
}
}
impl<'a> SliceArgs<'a> for (&'a str, usize) {
fn get(self) -> Args<'a> {
(0, self.0, self.1)
}
}
impl<'a> SliceArgs<'a> for (usize, &'a String, usize) {
fn get(self) -> Args<'a> {
(self.0, self.1, self.2)
}
}
impl<'a> SliceArgs<'a> for (usize, &'a String) {
fn get(self) -> Args<'a> {
(self.0, self.1 as &'a str).get()
}
}
impl<'a> SliceArgs<'a> for (&'a String, usize) {
fn get(self) -> Args<'a> {
(self.0 as &'a str, self.1).get()
}
}
impl<'a, F: Fn(char) -> bool> SliceArgs<'a> for (F, &'a str) {
fn get(self) -> Args<'a> {
let (f, s) = self;
let at = find(s, f);
(at, s, s.len())
}
}
impl<'a, F: Fn(char) -> bool> SliceArgs<'a> for (&'a str, F) {
fn get(self) -> Args<'a> {
let (s, f) = self;
let at = find(s, f);
(0, s, at)
}
}
impl<'a, F: Fn(char) -> bool> SliceArgs<'a> for (F, &'a str, F) {
fn get(self) -> Args<'a> {
let (f1, s, f2) = self;
let beg = find(s, f1);
let end = find(s, f2);
(beg, s, end)
}
}
impl<'a, F: Fn(char) -> bool> SliceArgs<'a> for (F, &'a String) {
fn get(self) -> Args<'a> {
(self.0, self.1 as &'a str).get()
}
}
impl<'a, F: Fn(char) -> bool> SliceArgs<'a> for (&'a String, F) {
fn get(self) -> Args<'a> {
(self.0 as &'a str, self.1).get()
}
}
impl<'a, F: Fn(char) -> bool> SliceArgs<'a> for (F, &'a String, F) {
fn get(self) -> Args<'a> {
(self.0, self.1 as &'a str, self.2).get()
}
}
fn find<F: Fn(char) -> bool>(s: &str, f: F) -> usize {
match s.find(f) {
Some(at) => at,
None => s.len(),
}
}