Say tcx.lang_items() less

Author: jyn514

src/librustdoc/clean/utils.rs

@@ -352,29 +352,30 @@ pub fn qpath_to_string(p: &hir::QPath<'_>) -> String {
 pub fn impl_for_type(tcx: TyCtxt<'_>, primitive: PrimitiveType) -> Option<DefId> {
     use self::PrimitiveType::*;
 
+    let lang_items = tcx.lang_items();
     match primitive {
-        Isize => tcx.lang_items().isize_impl(),
-        I8 => tcx.lang_items().i8_impl(),
-        I16 => tcx.lang_items().i16_impl(),
-        I32 => tcx.lang_items().i32_impl(),
-        I64 => tcx.lang_items().i64_impl(),
-        I128 => tcx.lang_items().i128_impl(),
-        Usize => tcx.lang_items().usize_impl(),
-        U8 => tcx.lang_items().u8_impl(),
-        U16 => tcx.lang_items().u16_impl(),
-        U32 => tcx.lang_items().u32_impl(),
-        U64 => tcx.lang_items().u64_impl(),
-        U128 => tcx.lang_items().u128_impl(),
-        F32 => tcx.lang_items().f32_impl(),
-        F64 => tcx.lang_items().f64_impl(),
-        Char => tcx.lang_items().char_impl(),
-        Bool => tcx.lang_items().bool_impl(),
-        Str => tcx.lang_items().str_impl(),
-        Slice => tcx.lang_items().slice_impl(),
-        Array => tcx.lang_items().array_impl(),
+        Isize => lang_items.isize_impl(),
+        I8 => lang_items.i8_impl(),
+        I16 => lang_items.i16_impl(),
+        I32 => lang_items.i32_impl(),
+        I64 => lang_items.i64_impl(),
+        I128 => lang_items.i128_impl(),
+        Usize => lang_items.usize_impl(),
+        U8 => lang_items.u8_impl(),
+        U16 => lang_items.u16_impl(),
+        U32 => lang_items.u32_impl(),
+        U64 => lang_items.u64_impl(),
+        U128 => lang_items.u128_impl(),
+        F32 => lang_items.f32_impl(),
+        F64 => lang_items.f64_impl(),
+        Char => lang_items.char_impl(),
+        Bool => lang_items.bool_impl(),
+        Str => lang_items.str_impl(),
+        Slice => lang_items.slice_impl(),
+        Array => lang_items.array_impl(),
         Tuple => None,
         Unit => None,
-        RawPointer => tcx.lang_items().const_ptr_impl(),
+        RawPointer => lang_items.const_ptr_impl(),
         Reference => None,
         Fn => None,
         Never => None,