Document pre-Rust-2021 special case for IntoIterator method lookup
This is the #[rustc_skip_array_during_method_dispatch] special case.
@@ -66,6 +66,11 @@ Once a method is looked up, if it can't be called for one (or more) of those rea
If a step is reached where there is more than one possible method, such as where generic methods or traits are considered the same, then it is a compiler error.
These cases require a [disambiguating function call syntax] for method and function invocation.
+> **Edition Differences**: Before the 2021 edition, during the search for visible methods, if the candidate receiver type is an [array type], methods provided by the standard library [`IntoIterator`] trait are ignored.
+>
+> The edition used for this purpose is determined by the token representing the method name.
+
+
<div class="warning">
***Warning:*** For [trait objects], if there is an inherent method of the same name as a trait method, it will give a compiler error when trying to call the method in a method call expression.
@@ -79,9 +84,11 @@ Just don't define inherent methods on trait objects with the same name as a trai
[_Expression_]: ../expressions.md
[_PathExprSegment_]: ../paths.md#paths-in-expressions
[visible]: ../visibility-and-privacy.md
+[array type]: ../types/array.md
[trait objects]: ../types/trait-object.md
[disambiguate call]: call-expr.md#disambiguating-function-calls
[disambiguating function call syntax]: call-expr.md#disambiguating-function-calls
[dereference]: operator-expr.md#the-dereference-operator
[methods]: ../items/associated-items.md#methods
[unsized coercion]: ../type-coercions.md#unsized-coercions
+[`IntoIterator`]: ../../std/iter/trait.IntoIterator.html
