Fix doc tests
diff --git a/src/doc/trpl/associated-constants.md b/src/doc/trpl/associated-constants.md
index 1c097be..2f23af5 100644
--- a/src/doc/trpl/associated-constants.md
+++ b/src/doc/trpl/associated-constants.md
@@ -2,7 +2,7 @@
With the `associated_consts` feature, you can define constants like this:
-```rust
+```rust,ignore
#![feature(associated_consts)]
trait Foo {
@@ -41,7 +41,7 @@
A default value can be implemented as well:
-```rust
+```rust,ignore
#![feature(associated_consts)]
trait Foo {
@@ -68,7 +68,7 @@
Associated constants don’t have to be associated with a trait. An `impl` block
for a `struct` works fine too:
-```rust
+```rust,ignore
#![feature(associated_consts)]
struct Foo;
