Cannot run command to create flat table #24

When I run the command 'php artisan eav:compile:entity product' to create the flat table I get the following error:

Compiling product entity.
Creating flat table for products.
in C:\Websites\eavproject\database/migrations/eav/products_flat.php
Found 14 attributes.

In products_flat.php line 18:

syntax error, unexpected '(', expecting identifier (T_STRING) or variable (T_VARIABLE) or '{' or '$'

And it creates the products_flat.php with the following syntax errors:

....
....
public function up()
{
Schema::dropIfExists('products_flat');
Schema::create('products_flat', function (Blueprint $table) {
$table->('');
$table->string()('accessible_furniture_shape')->nullable();
$table->string()('item_weight_kg')->nullable();
$table->string()('strength_options')->nullable();
$table->string()('size')->nullable()->default('s');
$table->string()('length')->nullable();
$table->string()('width')->nullable();
$table->string()('item_weight_g')->nullable();
$table->int('featured_product')->nullable();
$table->string()('garden_tool_type')->nullable();
$table->string()('accessible_furniture_material')->nullable();
$table->int('garden_stool_arms')->nullable();
$table->string()('color_options')->nullable();
$table->string()('garden_tools_material')->nullable();
$table->string()('weight')->nullable();
});
}

.....

Any idea why is this happening? Thanks.