Use :binary.split/2 instead of part+match

2 files changed, 5 insertions, 10 deletions

diff --git a/lib/elixir/lib/string.ex b/lib/elixir/lib/string.ex
index 2d96ed999..d37daeac0 100644
--- a/lib/elixir/lib/string.ex
+++ b/lib/elixir/lib/string.ex
@@ -430,15 +430,10 @@ defmodule String do
   end
 
   defp do_splitter(bin, pattern, trim) do
-    case :binary.match(bin, pattern) do
-      {0, length} when trim ->
-        do_splitter(:binary.part(bin, length, byte_size(bin) - length), pattern, trim)
-      {pos, length} ->
-        final = pos + length
-        {:binary.part(bin, 0, pos),
-         :binary.part(bin, final, byte_size(bin) - final)}
-      :nomatch ->
-        {bin, :nomatch}
+    case :binary.split(bin, pattern) do
+      ["", second] when trim -> do_splitter(second, pattern, trim)
+      [first, second] -> {first, second}
+      [first] -> {first, :nomatch}
     end
   end
 
diff --git a/lib/elixir/lib/string_io.ex b/lib/elixir/lib/string_io.ex
index 2552494f5..ca4e253d9 100644
--- a/lib/elixir/lib/string_io.ex
+++ b/lib/elixir/lib/string_io.ex
@@ -266,7 +266,7 @@ defmodule StringIO do
       {:replace_split, count} ->
         {result, remainder} = :erlang.split_binary(input, count)
 
-        {:erlang.binary_part(result, 0, byte_size(result) - 2) <> "\n", state_after_read(s, remainder, prompt)}
+        {binary_part(result, 0, byte_size(result) - 2) <> "\n", state_after_read(s, remainder, prompt)}
       :error
         -> {{:error, :collect_line}, s}
     end