// Copyright 2014 The Rust Project Developers. See the COPYRIGHT // file at the top-level directory of this distribution and at // http://rust-lang.org/COPYRIGHT. // // Licensed under the Apache License, Version 2.0 or the MIT license // , at your // option. This file may not be copied, modified, or distributed // except according to those terms. // As dst-struct.rs, but the unsized field is the only field in the struct. struct Fat { ptr: T } // x is a fat pointer fn foo(x: &Fat<[int]>) { let y = &x.ptr; assert!(x.ptr.len() == 3); assert!(y[0] == 1); assert!(x.ptr[1] == 2); } fn foo2(x: &Fat<[T]>) { let y = &x.ptr; let bar = Bar; assert!(x.ptr.len() == 3); assert!(y[0].to_bar() == bar); assert!(x.ptr[1].to_bar() == bar); } #[deriving(PartialEq,Eq)] struct Bar; trait ToBar { fn to_bar(&self) -> Bar; } impl ToBar for Bar { fn to_bar(&self) -> Bar { *self } } pub fn main() { // With a vec of ints. let f1 = Fat { ptr: [1, 2, 3] }; foo(&f1); let f2 = &f1; foo(f2); let f3: &Fat<[int]> = f2; foo(f3); let f4: &Fat<[int]> = &f1; foo(f4); let f5: &Fat<[int]> = &Fat { ptr: [1, 2, 3] }; foo(f5); // With a vec of Bars. let bar = Bar; let f1 = Fat { ptr: [bar, bar, bar] }; foo2(&f1); let f2 = &f1; foo2(f2); let f3: &Fat<[Bar]> = f2; foo2(f3); let f4: &Fat<[Bar]> = &f1; foo2(f4); let f5: &Fat<[Bar]> = &Fat { ptr: [bar, bar, bar] }; foo2(f5); // Assignment. let f5: &mut Fat<[int]> = &mut Fat { ptr: [1, 2, 3] }; f5.ptr[1] = 34; assert!(f5.ptr[0] == 1); assert!(f5.ptr[1] == 34); assert!(f5.ptr[2] == 3); // Zero size vec. let f5: &Fat<[int]> = &Fat { ptr: [] }; assert!(f5.ptr.len() == 0); let f5: &Fat<[Bar]> = &Fat { ptr: [] }; assert!(f5.ptr.len() == 0); }