add return annotations to pure functions

Author: WalterBright

std/algorithm/searching.d

@@ -1557,7 +1557,7 @@ Returns:
 
 See_ALso: $(LREF findAdjacent), $(LREF findAmong), $(LREF findSkip), $(LREF findSplit), $(LREF startsWith)
 */
-InputRange find(alias pred = "a == b", InputRange, Element)(InputRange haystack, scope Element needle)
+InputRange find(alias pred = "a == b", InputRange, Element)(return InputRange haystack, scope Element needle)
 if (isInputRange!InputRange &&
     is (typeof(binaryFun!pred(haystack.front, needle)) : bool) &&
    !is (typeof(binaryFun!pred(haystack.front, needle.front)) : bool))
@@ -1602,7 +1602,7 @@ if (isInputRange!InputRange &&
             {
                 if (!__ctfe && canSearchInCodeUnits!char(needle))
                 {
-                    static R trustedMemchr(ref R haystack, ref E needle) @trusted nothrow pure
+                    static R trustedMemchr(return ref R haystack, ref E needle) @trusted nothrow pure
                     {
                         import core.stdc.string : memchr;
                         auto ptr = memchr(haystack.ptr, needle, haystack.length);

std/bigint.d

@@ -211,7 +211,7 @@ public:
      * Implements assignment operators from built-in integers of the form
      * `BigInt op= integer`.
      */
-    BigInt opOpAssign(string op, T)(T y) pure nothrow @safe
+    BigInt opOpAssign(string op, T)(T y) return pure nothrow @safe
         if ((op=="+" || op=="-" || op=="*" || op=="/" || op=="%"
           || op==">>" || op=="<<" || op=="^^" || op=="|" || op=="&" || op=="^") && isIntegral!T)
     {
@@ -363,7 +363,7 @@ public:
     /**
      * Implements assignment operators of the form `BigInt op= BigInt`.
      */
-    BigInt opOpAssign(string op, T)(T y) pure nothrow @safe
+    BigInt opOpAssign(string op, T)(T y) return pure nothrow @safe
         if ((op=="+" || op== "-" || op=="*" || op=="|" || op=="&" || op=="^" || op=="/" || op=="%")
             && is (T: BigInt))
     {

std/bitmanip.d

@@ -1515,7 +1515,7 @@ public:
     /**********************************************
      * Reverses the bits of the `BitArray`.
      */
-    @property BitArray reverse() @nogc pure nothrow
+    @property BitArray reverse() return @nogc pure nothrow
     out (result)
     {
         assert(result == this, "the result must be equal to this");
@@ -1555,7 +1555,7 @@ public:
     /**********************************************
      * Sorts the `BitArray`'s elements.
      */
-    @property BitArray sort() @nogc pure nothrow
+    @property BitArray sort() return @nogc pure nothrow
     out (result)
     {
         assert(result == this, "the result must be equal to this");