src/test/ui/higher-lifetime-bounds.rs

   1 // Copyright 2014 The Rust Project Developers. See the COPYRIGHT
   2 // file at the top-level directory of this distribution and at
   3 // http://rust-lang.org/COPYRIGHT.
   4 //
   5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
   6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
   8 // option. This file may not be copied, modified, or distributed
   9 // except according to those terms.
  10
  11 #![allow(dead_code, non_camel_case_types)]
  12
  13 // Test that bounds on higher-kinded lifetime binders are rejected.
  14
  15 fn bar1<'a, 'b>(
  16     x: &'a i32,
  17     y: &'b i32,
  18     f: for<'xa, 'xb: 'xa+'xa> fn(&'xa i32, &'xb i32) -> &'xa i32)
  19     //~^ ERROR lifetime bounds cannot be used in this context
  20 {
  21     // If the bound in f's type would matter, the call below would (have to)
  22     // be rejected.
  23     f(x, y);
  24 }
  25
  26 fn bar2<'a, 'b, F: for<'xa, 'xb: 'xa> Fn(&'xa i32, &'xb i32) -> &'xa i32>(
  27     //~^ ERROR lifetime bounds cannot be used in this context
  28     x: &'a i32,
  29     y: &'b i32,
  30     f: F)
  31 {
  32     // If the bound in f's type would matter, the call below would (have to)
  33     // be rejected.
  34     f(x, y);
  35 }
  36
  37 fn bar3<'a, 'b, F>(
  38     x: &'a i32,
  39     y: &'b i32,
  40     f: F)
  41     where F: for<'xa, 'xb: 'xa> Fn(&'xa i32, &'xb i32) -> &'xa i32
  42     //~^ ERROR lifetime bounds cannot be used in this context
  43 {
  44     // If the bound in f's type would matter, the call below would (have to)
  45     // be rejected.
  46     f(x, y);
  47 }
  48
  49 fn bar4<'a, 'b, F>(
  50     x: &'a i32,
  51     y: &'b i32,
  52     f: F)
  53     where for<'xa, 'xb: 'xa> F: Fn(&'xa i32, &'xb i32) -> &'xa i32
  54     //~^ ERROR lifetime bounds cannot be used in this context
  55 {
  56     // If the bound in f's type would matter, the call below would (have to)
  57     // be rejected.
  58     f(x, y);
  59 }
  60
  61 struct S1<F: for<'xa, 'xb: 'xa> Fn(&'xa i32, &'xb i32) -> &'xa i32>(F);
  62 //~^ ERROR lifetime bounds cannot be used in this context
  63 struct S2<F>(F) where F: for<'xa, 'xb: 'xa> Fn(&'xa i32, &'xb i32) -> &'xa i32;
  64 //~^ ERROR lifetime bounds cannot be used in this context
  65 struct S3<F>(F) where for<'xa, 'xb: 'xa> F: Fn(&'xa i32, &'xb i32) -> &'xa i32;
  66 //~^ ERROR lifetime bounds cannot be used in this context
  67
  68 struct S_fnty(for<'xa, 'xb: 'xa> fn(&'xa i32, &'xb i32) -> &'xa i32);
  69 //~^ ERROR lifetime bounds cannot be used in this context
  70
  71 type T1 = Box<for<'xa, 'xb: 'xa> Fn(&'xa i32, &'xb i32) -> &'xa i32>;
  72 //~^ ERROR lifetime bounds cannot be used in this context
  73
  74 fn main() {
  75     let _ : Option<for<'xa, 'xb: 'xa> fn(&'xa i32, &'xb i32) -> &'xa i32> = None;
  76     //~^ ERROR lifetime bounds cannot be used in this context
  77     let _ : Option<Box<for<'xa, 'xb: 'xa> Fn(&'xa i32, &'xb i32) -> &'xa i32>> = None;
  78     //~^ ERROR lifetime bounds cannot be used in this context
  79 }