title: Unexpected end of macro invocation in Rust
body: <p>I have the following code in Rust</p>
  
  <pre><code>use std::fmt;
  
  pub struct MyRange&lt;Idx&gt; {
      pub start: Idx,
      pub end: Idx,
  }
  
  impl fmt::Debug for MyRange&lt;f32&gt;  {
      fn fmt( &amp;self, f: &amp;mut fmt::Formatter ) -&gt; fmt::Result {
          write!( "Nothing seriously" )
      }
  }
  
  fn main() {
      let start:f32= 1.2;
      let end:f32 = 5.;
      let rng2 = MyRange { start: start, end: end};
      println!( "{:?}", rng2 ); 
  }
  </code></pre>
  
  <p>At Compile, I'm getting the following error</p>
  
  <pre><code>error: unexpected end of macro invocation
    --&gt; src/main.rs:10:17
     |
  10 |         write!( "Nothing seriously" )
     |                 ^^^^^^^^^^^^^^^^^^^
  </code></pre>
  
  <p>I'm not exactly certain what the problem is.</p>
  
  <p>Edit: I'm using the latest Rust version (Stable 1.20)</p>