<p dir="auto">This code:</p>
<div class="highlight highlight-source-rust notranslate position-relative overflow-auto" dir="auto" data-snippet-clipboard-copy-content="fn main() {
    let vec = vec![1,4,35,13,42,1];
    for x in vec[3..] {
        print!(&quot;{} &quot;, x);
    }
}"><pre class="notranslate"><span class="pl-k">fn</span> <span class="pl-en">main</span><span class="pl-kos">(</span><span class="pl-kos">)</span> <span class="pl-kos">{</span>
    <span class="pl-k">let</span> vec = <span class="pl-en">vec</span><span class="pl-en">!</span><span class="pl-kos">[</span><span class="pl-c1">1</span>,<span class="pl-c1">4</span>,<span class="pl-c1">35</span>,<span class="pl-c1">13</span>,<span class="pl-c1">42</span>,<span class="pl-c1">1</span><span class="pl-kos">]</span><span class="pl-kos">;</span>
    <span class="pl-k">for</span> x <span class="pl-k">in</span> vec<span class="pl-kos">[</span><span class="pl-c1">3</span>..<span class="pl-kos">]</span> <span class="pl-kos">{</span>
        <span class="pl-en">print</span><span class="pl-en">!</span><span class="pl-kos">(</span><span class="pl-s">"{} "</span>, x<span class="pl-kos">)</span><span class="pl-kos">;</span>
    <span class="pl-kos">}</span>
<span class="pl-kos">}</span></pre></div>
<p dir="auto">produces the following errors</p>
<div class="snippet-clipboard-content notranslate position-relative overflow-auto" data-snippet-clipboard-copy-content="main.rs:3:5: 5:6 error: the trait `core::marker::Sized` is not implemented for the type `[_]` [E0277]
main.rs:3     for x in vec[3..] {
main.rs:4         print!(&quot;{} &quot;, x);
main.rs:5     }
note: in expansion of for loop expansion
main.rs:3:5: 5:6 note: expansion site
main.rs:3:5: 5:6 note: `[_]` does not have a constant size known at compile-time
main.rs:3     for x in vec[3..] {
main.rs:4         print!(&quot;{} &quot;, x);
main.rs:5     }
note: in expansion of for loop expansion
main.rs:3:5: 5:6 note: expansion site
main.rs:3:5: 5:6 error: the trait `core::iter::Iterator` is not implemented for the type `[_]` [E0277]
main.rs:3     for x in vec[3..] {
main.rs:4         print!(&quot;{} &quot;, x);
main.rs:5     }
note: in expansion of for loop expansion
main.rs:3:5: 5:6 note: expansion site
main.rs:3:5: 5:6 note: `[_]` is not an iterator; maybe try calling `.iter()` or a similar method
main.rs:3     for x in vec[3..] {
main.rs:4         print!(&quot;{} &quot;, x);
main.rs:5     }
note: in expansion of for loop expansion
main.rs:3:5: 5:6 note: expansion site
main.rs:3:5: 5:6 error: the trait `core::marker::Sized` is not implemented for the type `[_]` [E0277]
main.rs:3     for x in vec[3..] {
main.rs:4         print!(&quot;{} &quot;, x);
main.rs:5     }
note: in expansion of for loop expansion
main.rs:3:5: 5:6 note: expansion site
main.rs:3:5: 5:6 note: `[_]` does not have a constant size known at compile-time
main.rs:3     for x in vec[3..] {
main.rs:4         print!(&quot;{} &quot;, x);
main.rs:5     }
note: in expansion of for loop expansion
main.rs:3:5: 5:6 note: expansion site
main.rs:3:5: 5:6 error: the trait `core::marker::Sized` is not implemented for the type `[_]` [E0277]
main.rs:3     for x in vec[3..] {
main.rs:4         print!(&quot;{} &quot;, x);
main.rs:5     }
note: in expansion of for loop expansion
main.rs:3:5: 5:6 note: expansion site
main.rs:3:5: 5:6 note: `[_]` does not have a constant size known at compile-time
main.rs:3     for x in vec[3..] {
main.rs:4         print!(&quot;{} &quot;, x);
main.rs:5     }
note: in expansion of for loop expansion
main.rs:3:5: 5:6 note: expansion site
main.rs:3:5: 5:6 error: the trait `core::iter::Iterator` is not implemented for the type `[_]` [E0277]
main.rs:3     for x in vec[3..] {
main.rs:4         print!(&quot;{} &quot;, x);
main.rs:5     }
note: in expansion of for loop expansion
main.rs:3:5: 5:6 note: expansion site
main.rs:3:5: 5:6 note: `[_]` is not an iterator; maybe try calling `.iter()` or a similar method
main.rs:3     for x in vec[3..] {
main.rs:4         print!(&quot;{} &quot;, x);
main.rs:5     }
note: in expansion of for loop expansion
main.rs:3:5: 5:6 note: expansion site
main.rs:3:5: 5:6 error: the trait `core::iter::Iterator` is not implemented for the type `[_]` [E0277]
main.rs:3     for x in vec[3..] {
main.rs:4         print!(&quot;{} &quot;, x);
main.rs:5     }
note: in expansion of for loop expansion
main.rs:3:5: 5:6 note: expansion site
main.rs:3:5: 5:6 note: `[_]` is not an iterator; maybe try calling `.iter()` or a similar method
main.rs:3     for x in vec[3..] {
main.rs:4         print!(&quot;{} &quot;, x);
main.rs:5     }
note: in expansion of for loop expansion
main.rs:3:5: 5:6 note: expansion site
error: aborting due to 6 previous errors"><pre class="notranslate"><code class="notranslate">main.rs:3:5: 5:6 error: the trait `core::marker::Sized` is not implemented for the type `[_]` [E0277]
main.rs:3     for x in vec[3..] {
main.rs:4         print!("{} ", x);
main.rs:5     }
note: in expansion of for loop expansion
main.rs:3:5: 5:6 note: expansion site
main.rs:3:5: 5:6 note: `[_]` does not have a constant size known at compile-time
main.rs:3     for x in vec[3..] {
main.rs:4         print!("{} ", x);
main.rs:5     }
note: in expansion of for loop expansion
main.rs:3:5: 5:6 note: expansion site
main.rs:3:5: 5:6 error: the trait `core::iter::Iterator` is not implemented for the type `[_]` [E0277]
main.rs:3     for x in vec[3..] {
main.rs:4         print!("{} ", x);
main.rs:5     }
note: in expansion of for loop expansion
main.rs:3:5: 5:6 note: expansion site
main.rs:3:5: 5:6 note: `[_]` is not an iterator; maybe try calling `.iter()` or a similar method
main.rs:3     for x in vec[3..] {
main.rs:4         print!("{} ", x);
main.rs:5     }
note: in expansion of for loop expansion
main.rs:3:5: 5:6 note: expansion site
main.rs:3:5: 5:6 error: the trait `core::marker::Sized` is not implemented for the type `[_]` [E0277]
main.rs:3     for x in vec[3..] {
main.rs:4         print!("{} ", x);
main.rs:5     }
note: in expansion of for loop expansion
main.rs:3:5: 5:6 note: expansion site
main.rs:3:5: 5:6 note: `[_]` does not have a constant size known at compile-time
main.rs:3     for x in vec[3..] {
main.rs:4         print!("{} ", x);
main.rs:5     }
note: in expansion of for loop expansion
main.rs:3:5: 5:6 note: expansion site
main.rs:3:5: 5:6 error: the trait `core::marker::Sized` is not implemented for the type `[_]` [E0277]
main.rs:3     for x in vec[3..] {
main.rs:4         print!("{} ", x);
main.rs:5     }
note: in expansion of for loop expansion
main.rs:3:5: 5:6 note: expansion site
main.rs:3:5: 5:6 note: `[_]` does not have a constant size known at compile-time
main.rs:3     for x in vec[3..] {
main.rs:4         print!("{} ", x);
main.rs:5     }
note: in expansion of for loop expansion
main.rs:3:5: 5:6 note: expansion site
main.rs:3:5: 5:6 error: the trait `core::iter::Iterator` is not implemented for the type `[_]` [E0277]
main.rs:3     for x in vec[3..] {
main.rs:4         print!("{} ", x);
main.rs:5     }
note: in expansion of for loop expansion
main.rs:3:5: 5:6 note: expansion site
main.rs:3:5: 5:6 note: `[_]` is not an iterator; maybe try calling `.iter()` or a similar method
main.rs:3     for x in vec[3..] {
main.rs:4         print!("{} ", x);
main.rs:5     }
note: in expansion of for loop expansion
main.rs:3:5: 5:6 note: expansion site
main.rs:3:5: 5:6 error: the trait `core::iter::Iterator` is not implemented for the type `[_]` [E0277]
main.rs:3     for x in vec[3..] {
main.rs:4         print!("{} ", x);
main.rs:5     }
note: in expansion of for loop expansion
main.rs:3:5: 5:6 note: expansion site
main.rs:3:5: 5:6 note: `[_]` is not an iterator; maybe try calling `.iter()` or a similar method
main.rs:3     for x in vec[3..] {
main.rs:4         print!("{} ", x);
main.rs:5     }
note: in expansion of for loop expansion
main.rs:3:5: 5:6 note: expansion site
error: aborting due to 6 previous errors
</code></pre></div>
<p dir="auto">Both the Sized and Iterator errors repeat multiple times, and I suspect they would repeat indefinitely if rustc didn't have an error threshold.</p>
<div class="snippet-clipboard-content notranslate position-relative overflow-auto" data-snippet-clipboard-copy-content="fn main() {
    let buf: &amp;[u8] = &amp;[12, 13, 14, 15, 16];
    let indices = buf.iter().zip(buf.iter().skip(1)).enumerate().filter(|_, (a, b)| *a == b'\r' &amp;&amp; *b == b'\n').map(|(i, (_, _))| i);

    for i in indices {
        // ...
    }
}"><pre class="notranslate"><code class="notranslate">fn main() {
    let buf: &amp;[u8] = &amp;[12, 13, 14, 15, 16];
    let indices = buf.iter().zip(buf.iter().skip(1)).enumerate().filter(|_, (a, b)| *a == b'\r' &amp;&amp; *b == b'\n').map(|(i, (_, _))| i);

    for i in indices {
        // ...
    }
}
</code></pre></div>
<p dir="auto">Building the above produces 48 errors. Removing the map at the end results in <em>only</em> 20 error messages and adding another gives me 112!</p>
<p dir="auto">Playpen: <a href="http://is.gd/zEJAf8" rel="nofollow">http://is.gd/zEJAf8</a></p>
<div class="snippet-clipboard-content notranslate position-relative overflow-auto" data-snippet-clipboard-copy-content="&lt;anon&gt;:3:85: 3:87 error: the type of this value must be known in this context
&lt;anon&gt;:3     let indices = buf.iter().zip(buf.iter().skip(1)).enumerate().filter(|_, (a, b)| *a == b'\r' &amp;&amp; *b == b'\n').map(|(i, (_, _))| i);
                                                                                             ^~
note: in expansion of closure expansion
&lt;anon&gt;:3:73: 3:111 note: expansion site
&lt;anon&gt;:3:100: 3:102 error: the type of this value must be known in this context
&lt;anon&gt;:3     let indices = buf.iter().zip(buf.iter().skip(1)).enumerate().filter(|_, (a, b)| *a == b'\r' &amp;&amp; *b == b'\n').map(|(i, (_, _))| i);
                                                                                                            ^~
note: in expansion of closure expansion
&lt;anon&gt;:3:73: 3:111 note: expansion site
&lt;anon&gt;:3:113: 3:133 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:3     let indices = buf.iter().zip(buf.iter().skip(1)).enumerate().filter(|_, (a, b)| *a == b'\r' &amp;&amp; *b == b'\n').map(|(i, (_, _))| i);
                                                                                                                         ^~~~~~~~~~~~~~~~~~~~
&lt;anon&gt;:3:113: 3:133 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:3     let indices = buf.iter().zip(buf.iter().skip(1)).enumerate().filter(|_, (a, b)| *a == b'\r' &amp;&amp; *b == b'\n').map(|(i, (_, _))| i);
                                                                                                                         ^~~~~~~~~~~~~~~~~~~~
&lt;anon&gt;:3:113: 3:133 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:3     let indices = buf.iter().zip(buf.iter().skip(1)).enumerate().filter(|_, (a, b)| *a == b'\r' &amp;&amp; *b == b'\n').map(|(i, (_, _))| i);
                                                                                                                         ^~~~~~~~~~~~~~~~~~~~
&lt;anon&gt;:3:113: 3:133 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:3     let indices = buf.iter().zip(buf.iter().skip(1)).enumerate().filter(|_, (a, b)| *a == b'\r' &amp;&amp; *b == b'\n').map(|(i, (_, _))| i);
                                                                                                                         ^~~~~~~~~~~~~~~~~~~~
&lt;anon&gt;:3:113: 3:133 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:3     let indices = buf.iter().zip(buf.iter().skip(1)).enumerate().filter(|_, (a, b)| *a == b'\r' &amp;&amp; *b == b'\n').map(|(i, (_, _))| i);
                                                                                                                         ^~~~~~~~~~~~~~~~~~~~
&lt;anon&gt;:3:113: 3:133 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:3     let indices = buf.iter().zip(buf.iter().skip(1)).enumerate().filter(|_, (a, b)| *a == b'\r' &amp;&amp; *b == b'\n').map(|(i, (_, _))| i);
                                                                                                                         ^~~~~~~~~~~~~~~~~~~~
&lt;anon&gt;:3:113: 3:133 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:3     let indices = buf.iter().zip(buf.iter().skip(1)).enumerate().filter(|_, (a, b)| *a == b'\r' &amp;&amp; *b == b'\n').map(|(i, (_, _))| i);
                                                                                                                         ^~~~~~~~~~~~~~~~~~~~
&lt;anon&gt;:3:113: 3:133 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:3     let indices = buf.iter().zip(buf.iter().skip(1)).enumerate().filter(|_, (a, b)| *a == b'\r' &amp;&amp; *b == b'\n').map(|(i, (_, _))| i);
                                                                                                                         ^~~~~~~~~~~~~~~~~~~~
&lt;anon&gt;:3:66: 3:112 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:3     let indices = buf.iter().zip(buf.iter().skip(1)).enumerate().filter(|_, (a, b)| *a == b'\r' &amp;&amp; *b == b'\n').map(|(i, (_, _))| i);
                                                                          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
&lt;anon&gt;:3:66: 3:112 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:3     let indices = buf.iter().zip(buf.iter().skip(1)).enumerate().filter(|_, (a, b)| *a == b'\r' &amp;&amp; *b == b'\n').map(|(i, (_, _))| i);
                                                                          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 note: required by `core::iter::IntoIterator::into_iter`
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 note: required by `core::iter::IntoIterator::into_iter`
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 note: required by `core::iter::IntoIterator::into_iter`
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 note: required by `core::iter::IntoIterator::into_iter`
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 note: required by `core::iter::IntoIterator::into_iter`
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 note: required by `core::iter::IntoIterator::into_iter`
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 note: required by `core::iter::IntoIterator::into_iter`
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 note: required by `core::iter::IntoIterator::into_iter`
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 note: required by `core::iter::Iterator::next`
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 note: required by `core::iter::Iterator::next`
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 note: required by `core::iter::Iterator::next`
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 note: required by `core::iter::Iterator::next`
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
error: aborting due to 48 previous errors
playpen: application terminated with error code 101"><pre class="notranslate"><code class="notranslate">&lt;anon&gt;:3:85: 3:87 error: the type of this value must be known in this context
&lt;anon&gt;:3     let indices = buf.iter().zip(buf.iter().skip(1)).enumerate().filter(|_, (a, b)| *a == b'\r' &amp;&amp; *b == b'\n').map(|(i, (_, _))| i);
                                                                                             ^~
note: in expansion of closure expansion
&lt;anon&gt;:3:73: 3:111 note: expansion site
&lt;anon&gt;:3:100: 3:102 error: the type of this value must be known in this context
&lt;anon&gt;:3     let indices = buf.iter().zip(buf.iter().skip(1)).enumerate().filter(|_, (a, b)| *a == b'\r' &amp;&amp; *b == b'\n').map(|(i, (_, _))| i);
                                                                                                            ^~
note: in expansion of closure expansion
&lt;anon&gt;:3:73: 3:111 note: expansion site
&lt;anon&gt;:3:113: 3:133 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:3     let indices = buf.iter().zip(buf.iter().skip(1)).enumerate().filter(|_, (a, b)| *a == b'\r' &amp;&amp; *b == b'\n').map(|(i, (_, _))| i);
                                                                                                                         ^~~~~~~~~~~~~~~~~~~~
&lt;anon&gt;:3:113: 3:133 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:3     let indices = buf.iter().zip(buf.iter().skip(1)).enumerate().filter(|_, (a, b)| *a == b'\r' &amp;&amp; *b == b'\n').map(|(i, (_, _))| i);
                                                                                                                         ^~~~~~~~~~~~~~~~~~~~
&lt;anon&gt;:3:113: 3:133 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:3     let indices = buf.iter().zip(buf.iter().skip(1)).enumerate().filter(|_, (a, b)| *a == b'\r' &amp;&amp; *b == b'\n').map(|(i, (_, _))| i);
                                                                                                                         ^~~~~~~~~~~~~~~~~~~~
&lt;anon&gt;:3:113: 3:133 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:3     let indices = buf.iter().zip(buf.iter().skip(1)).enumerate().filter(|_, (a, b)| *a == b'\r' &amp;&amp; *b == b'\n').map(|(i, (_, _))| i);
                                                                                                                         ^~~~~~~~~~~~~~~~~~~~
&lt;anon&gt;:3:113: 3:133 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:3     let indices = buf.iter().zip(buf.iter().skip(1)).enumerate().filter(|_, (a, b)| *a == b'\r' &amp;&amp; *b == b'\n').map(|(i, (_, _))| i);
                                                                                                                         ^~~~~~~~~~~~~~~~~~~~
&lt;anon&gt;:3:113: 3:133 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:3     let indices = buf.iter().zip(buf.iter().skip(1)).enumerate().filter(|_, (a, b)| *a == b'\r' &amp;&amp; *b == b'\n').map(|(i, (_, _))| i);
                                                                                                                         ^~~~~~~~~~~~~~~~~~~~
&lt;anon&gt;:3:113: 3:133 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:3     let indices = buf.iter().zip(buf.iter().skip(1)).enumerate().filter(|_, (a, b)| *a == b'\r' &amp;&amp; *b == b'\n').map(|(i, (_, _))| i);
                                                                                                                         ^~~~~~~~~~~~~~~~~~~~
&lt;anon&gt;:3:113: 3:133 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:3     let indices = buf.iter().zip(buf.iter().skip(1)).enumerate().filter(|_, (a, b)| *a == b'\r' &amp;&amp; *b == b'\n').map(|(i, (_, _))| i);
                                                                                                                         ^~~~~~~~~~~~~~~~~~~~
&lt;anon&gt;:3:66: 3:112 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:3     let indices = buf.iter().zip(buf.iter().skip(1)).enumerate().filter(|_, (a, b)| *a == b'\r' &amp;&amp; *b == b'\n').map(|(i, (_, _))| i);
                                                                          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
&lt;anon&gt;:3:66: 3:112 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:3     let indices = buf.iter().zip(buf.iter().skip(1)).enumerate().filter(|_, (a, b)| *a == b'\r' &amp;&amp; *b == b'\n').map(|(i, (_, _))| i);
                                                                          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 note: required by `core::iter::IntoIterator::into_iter`
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 note: required by `core::iter::IntoIterator::into_iter`
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 note: required by `core::iter::IntoIterator::into_iter`
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 note: required by `core::iter::IntoIterator::into_iter`
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 note: required by `core::iter::IntoIterator::into_iter`
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 note: required by `core::iter::IntoIterator::into_iter`
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 note: required by `core::iter::IntoIterator::into_iter`
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 note: required by `core::iter::IntoIterator::into_iter`
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 note: required by `core::iter::Iterator::next`
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 note: required by `core::iter::Iterator::next`
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnMut&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 note: required by `core::iter::Iterator::next`
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 note: required by `core::iter::Iterator::next`
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
&lt;anon&gt;:5:5: 7:6 error: type mismatch: the type `[closure &lt;anon&gt;:3:73: 3:111]` implements the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)), ([type error], [type error]))&gt;`, but the trait `for&lt;'r&gt; core::ops::FnOnce&lt;(&amp;'r (usize, (&amp;u8, &amp;u8)),)&gt;` is required (expected a tuple with 1 elements, found one with 2 elements) [E0281]
&lt;anon&gt;:5     for i in indices {
&lt;anon&gt;:6         // ...
&lt;anon&gt;:7     }
note: in expansion of for loop expansion
&lt;anon&gt;:5:5: 7:6 note: expansion site
error: aborting due to 48 previous errors
playpen: application terminated with error code 101
</code></pre></div>