|  | // errorcheck | 
|  |  | 
|  | // Copyright 2009 The Go Authors. All rights reserved. | 
|  | // Use of this source code is governed by a BSD-style | 
|  | // license that can be found in the LICENSE file. | 
|  |  | 
|  | package main | 
|  |  | 
|  | var c1 chan <- chan int = (chan<- (chan int))(nil) | 
|  | var c2 chan <- chan int = (chan (<-chan int))(nil)  // ERROR "chan|incompatible" | 
|  | var c3 <- chan chan int = (<-chan (chan int))(nil) | 
|  | var c4 chan chan <- int = (chan (chan<- int))(nil) | 
|  |  | 
|  | var c5 <- chan <- chan int = (<-chan (<-chan int))(nil) | 
|  | var c6 chan <- <- chan int = (chan<- (<-chan int))(nil) | 
|  | var c7 chan <- chan <- int = (chan<- (chan<- int))(nil) | 
|  |  | 
|  | var c8 <- chan <- chan chan int = (<-chan (<-chan (chan int)))(nil) | 
|  | var c9 <- chan chan <- chan int = (<-chan (chan<- (chan int)))(nil) | 
|  | var c10 chan <- <- chan chan int = (chan<- (<-chan (chan int)))(nil) | 
|  | var c11 chan <- chan <- chan int = (chan<- (chan<- (chan int)))(nil) | 
|  | var c12 chan chan <- <- chan int = (chan (chan<- (<-chan int)))(nil) | 
|  | var c13 chan chan <- chan <- int = (chan (chan<- (chan<- int)))(nil) | 
|  |  | 
|  | var r1 chan<- (chan int) = (chan <- chan int)(nil) | 
|  | var r2 chan (<-chan int) = (chan <- chan int)(nil)  // ERROR "chan|incompatible" | 
|  | var r3 <-chan (chan int) = (<- chan chan int)(nil) | 
|  | var r4 chan (chan<- int) = (chan chan <- int)(nil) | 
|  |  | 
|  | var r5 <-chan (<-chan int) = (<- chan <- chan int)(nil) | 
|  | var r6 chan<- (<-chan int) = (chan <- <- chan int)(nil) | 
|  | var r7 chan<- (chan<- int) = (chan <- chan <- int)(nil) | 
|  |  | 
|  | var r8 <-chan (<-chan (chan int)) = (<- chan <- chan chan int)(nil) | 
|  | var r9 <-chan (chan<- (chan int)) = (<- chan chan <- chan int)(nil) | 
|  | var r10 chan<- (<-chan (chan int)) = (chan <- <- chan chan int)(nil) | 
|  | var r11 chan<- (chan<- (chan int)) = (chan <- chan <- chan int)(nil) | 
|  | var r12 chan (chan<- (<-chan int)) = (chan chan <- <- chan int)(nil) | 
|  | var r13 chan (chan<- (chan<- int)) = (chan chan <- chan <- int)(nil) |