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+### What it does
+As the counterpart to `or_fun_call`, this lint looks for unnecessary
+lazily evaluated closures on `Option` and `Result`.
+
+This lint suggests changing the following functions, when eager evaluation results in
+simpler code:
+ - `unwrap_or_else` to `unwrap_or`
+ - `and_then` to `and`
+ - `or_else` to `or`
+ - `get_or_insert_with` to `get_or_insert`
+ - `ok_or_else` to `ok_or`
+
+### Why is this bad?
+Using eager evaluation is shorter and simpler in some cases.
+
+### Known problems
+It is possible, but not recommended for `Deref` and `Index` to have
+side effects. Eagerly evaluating them can change the semantics of the program.
+
+### Example
+```
+// example code where clippy issues a warning
+let opt: Option<u32> = None;
+
+opt.unwrap_or_else(|| 42);
+```
+Use instead:
+```
+let opt: Option<u32> = None;
+
+opt.unwrap_or(42);
+```
+\ No newline at end of file