From cd977ee21787c38510b2a674673e022a7fd0a393 Mon Sep 17 00:00:00 2001 From: Edward Wang Date: Sat, 31 Jan 2015 22:19:13 +0800 Subject: Make sure type inference with `a..b` as good as `range(a,b)` The new `::ops::Range` has separated implementations for each of the numeric types, while the old `::iter::Range` has one for type `Int`. However, we do not take output bindings into account when selecting traits. So it confuses `typeck` and makes the new range does not work as good as the old one when it comes to type inference. This patch implements `Iterator` for the new range for one type `Int`. This limitation could be lifted, however, if we ever reconsider the output types' role in type inference. Closes #21595 Closes #21649 Closes #21672 --- src/test/run-pass/range-type-infer.rs | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) create mode 100644 src/test/run-pass/range-type-infer.rs (limited to 'src/test') diff --git a/src/test/run-pass/range-type-infer.rs b/src/test/run-pass/range-type-infer.rs new file mode 100644 index 00000000000..51945a4677d --- /dev/null +++ b/src/test/run-pass/range-type-infer.rs @@ -0,0 +1,28 @@ +// Copyright 2015 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. + +// Make sure the type inference for the new range expression work as +// good as the old one. Check out issue #21672, #21595 and #21649 for +// more details. + +fn main() { + let xs = (0..8).map(|i| i == 1u64).collect::>(); + assert_eq!(xs[1], true); + let xs = (0..8).map(|i| 1u64 == i).collect::>(); + assert_eq!(xs[1], true); + let xs: Vec = (0..10).collect(); + assert_eq!(xs.len(), 10); + + for x in 0..10 { x % 2; } + for x in 0..100 { x as f32; } + + let array = [true, false]; + for i in 0..1 { array[i]; } +} -- cgit 1.4.1-3-g733a5 From b9c055cc70816585ccd715f24b5fc965fe286174 Mon Sep 17 00:00:00 2001 From: Edward Wang Date: Sun, 1 Feb 2015 14:29:42 +0800 Subject: Fix fallout --- src/test/compile-fail/range-1.rs | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) (limited to 'src/test') diff --git a/src/test/compile-fail/range-1.rs b/src/test/compile-fail/range-1.rs index fbc9ad99b72..94903a11be0 100644 --- a/src/test/compile-fail/range-1.rs +++ b/src/test/compile-fail/range-1.rs @@ -17,10 +17,7 @@ pub fn main() { // Float => does not implement iterator. for i in 0f32..42f32 {} - //~^ ERROR `core::iter::Iterator` is not implemented for the type `core::ops::Range` - //~^^ ERROR - //~^^^ ERROR - // FIXME(#21528) not fulfilled obligation error should be reported once, not thrice + //~^ ERROR the trait `core::num::Int` is not implemented for the type `f32` // Unsized type. let arr: &[_] = &[1us, 2, 3]; -- cgit 1.4.1-3-g733a5