Can't Sprite using gulp.spritesmith

Question

Showing Error when I sprite,

I an new in gulp sprite, I need help,

this the error showing my console

Error in plugin 'sass'
Message:
    sass\custom\_sprite.scss
Error: index out of bounds for `nth($list, $n)`
        on line 421 of sass/custom/_sprite.scss
>>   width: nth($sprite, 5);

[12:50:49] Finished 'sass' after 507 ms

This is my include

I imported _sprite.scss in my scss file and Included Like this.

.jaba {
    i {
        @include sprite-width('facebook.png');
    }
}

Answer 1

The sprite mixin expects a spritesmith generated variable, not a string.

.jaba {
    i {
        @include sprite-width($facebook);
    }
}