bility. One can also re-declare mutability of a binding in
pattern matching. This is useful to avoid unnecessary <code>mut</code> annotations. An
interesting historical note is that Rust comes, syntactically, most closely
from ML, which also uses <code>let</code> to introduce bindings.</p>

<p>See also <a href="https://mail.mozilla.org/pipermail/rust-dev/2014-January/008319.html">a long thread</a> on renaming <code>let mut</code> to <code>var</code>.</p>

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