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// run-pass
#![allow(dead_code)]
use std::fmt::Display;
struct ST1(i32, i32);
impl ST1 {
fn new() -> Self {
ST1(0, 1)
}
fn ctor() -> Self {
Self(1,2) // Self as a constructor
}
fn pattern(self) {
match self {
Self(x, y) => println!("{} {}", x, y), // Self as a pattern
}
}
}
struct ST2<T>(T); // With type parameter
impl<T> ST2<T> where T: Display {
fn ctor(v: T) -> Self {
Self(v)
}
fn pattern(&self) {
match self {
Self(ref v) => println!("{}", v),
}
}
}
struct ST3<'a>(&'a i32); // With lifetime parameter
impl<'a> ST3<'a> {
fn ctor(v: &'a i32) -> Self {
Self(v)
}
fn pattern(self) {
let Self(ref v) = self;
println!("{}", v);
}
}
struct ST4(usize);
impl ST4 {
fn map(opt: Option<usize>) -> Option<Self> {
opt.map(Self) // use `Self` as a function passed somewhere
}
}
struct ST5; // unit struct
impl ST5 {
fn ctor() -> Self {
Self // `Self` as a unit struct value
}
fn pattern(self) -> Self {
match self {
Self => Self, // `Self` as a unit struct value for matching
}
}
}
struct ST6(i32);
type T = ST6;
impl T {
fn ctor() -> Self {
ST6(1)
}
fn type_alias(self) {
let Self(_x) = match self { Self(x) => Self(x) };
let _opt: Option<Self> = Some(0).map(Self);
}
}
struct ST7<T1, T2>(T1, T2);
impl ST7<i32, usize> {
fn ctor() -> Self {
Self(1, 2)
}
fn pattern(self) -> Self {
match self {
Self(x, y) => Self(x, y),
}
}
}
fn main() {
let v1 = ST1::ctor();
v1.pattern();
let v2 = ST2::ctor(10);
v2.pattern();
let local = 42;
let v3 = ST3::ctor(&local);
v3.pattern();
let v4 = Some(1usize);
let _ = ST4::map(v4);
let v5 = ST5::ctor();
v5.pattern();
let v6 = ST6::ctor();
v6.type_alias();
let v7 = ST7::<i32, usize>::ctor();
let r = v7.pattern();
println!("{} {}", r.0, r.1)
}
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