objective-c - iOS 同事写的创建代码的形式有点不认识

1. 同事写的创建控件的代码形式有点不认识...是masonry的特殊形式?

UIButton * button = ({
    button = [[UIButton alloc] init];
    button.backgroundColor = [UIColor lightGrayColor];
    [button setTitle:@"button" forState:UIControlStateNormal];
    [button addTarget:self action:@selector(button:) forControlEvents:UIControlEventTouchUpInside];
    
    button.layer.cornerRadius = 30.f;
    button.layer.masksToBounds = YES;
    [_bottomView addSubview:button];
    [button mas_makeConstraints:^(MASConstraintMaker *make) {
        make.centerY  . equalTo (button.mas_centerY);
        make.right    . equalTo (button.mas_left).offset(-10);
        make.width    . equalTo (@(60));
        make.height   . equalTo (@(60));
    }];
    button;
});