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diff --git a/src/tools/clippy/src/docs/redundant_pattern_matching.txt b/src/tools/clippy/src/docs/redundant_pattern_matching.txt
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+++ b/src/tools/clippy/src/docs/redundant_pattern_matching.txt
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+### What it does
+Lint for redundant pattern matching over `Result`, `Option`,
+`std::task::Poll` or `std::net::IpAddr`
+
+### Why is this bad?
+It's more concise and clear to just use the proper
+utility function
+
+### Known problems
+This will change the drop order for the matched type. Both `if let` and
+`while let` will drop the value at the end of the block, both `if` and `while` will drop the
+value before entering the block. For most types this change will not matter, but for a few
+types this will not be an acceptable change (e.g. locks). See the
+[reference](https://doc.rust-lang.org/reference/destructors.html#drop-scopes) for more about
+drop order.
+
+### Example
+```
+if let Ok(_) = Ok::<i32, i32>(42) {}
+if let Err(_) = Err::<i32, i32>(42) {}
+if let None = None::<()> {}
+if let Some(_) = Some(42) {}
+if let Poll::Pending = Poll::Pending::<()> {}
+if let Poll::Ready(_) = Poll::Ready(42) {}
+if let IpAddr::V4(_) = IpAddr::V4(Ipv4Addr::LOCALHOST) {}
+if let IpAddr::V6(_) = IpAddr::V6(Ipv6Addr::LOCALHOST) {}
+match Ok::<i32, i32>(42) {
+    Ok(_) => true,
+    Err(_) => false,
+};
+```
+
+The more idiomatic use would be:
+
+```
+if Ok::<i32, i32>(42).is_ok() {}
+if Err::<i32, i32>(42).is_err() {}
+if None::<()>.is_none() {}
+if Some(42).is_some() {}
+if Poll::Pending::<()>.is_pending() {}
+if Poll::Ready(42).is_ready() {}
+if IpAddr::V4(Ipv4Addr::LOCALHOST).is_ipv4() {}
+if IpAddr::V6(Ipv6Addr::LOCALHOST).is_ipv6() {}
+Ok::<i32, i32>(42).is_ok();
+```
+\ No newline at end of file