`std.mem.Allocator.create` replaced with better API

`std.mem.Allocator.createOne` is renamed to `std.mem.Allocator.create`.

The problem with the previous API is that even after copy elision,
the initalization value passed as a parameter would always be a copy.
With the new API, once copy elision is done, initialization
functions can directly initialize allocated memory in place.

Related:
 * #1872
 * #1873

1 files changed, 3 insertions, 2 deletions

diff --git a/std/io.zig b/std/io.zig
index 46625cd34b..c8701aeda6 100644
--- a/std/io.zig
+++ b/std/io.zig
@@ -944,12 +944,13 @@ pub const BufferedAtomicFile = struct {
 
     pub fn create(allocator: *mem.Allocator, dest_path: []const u8) !*BufferedAtomicFile {
         // TODO with well defined copy elision we don't need this allocation
-        var self = try allocator.create(BufferedAtomicFile{
+        var self = try allocator.create(BufferedAtomicFile);
+        self.* = BufferedAtomicFile{
             .atomic_file = undefined,
             .file_stream = undefined,
             .buffered_stream = undefined,
             .allocator = allocator,
-        });
+        };
         errdefer allocator.destroy(self);
 
         self.atomic_file = try os.AtomicFile.init(dest_path, os.File.default_mode);