Not a direct answer, but youtube-dl works with the video id also, like:
% yt OC1JiAUr3ZU

You may also "setopt nonomatch" to make zsh leave the argument unchanged if
no files match. Although, be warned that it might have some side effects.

Hope this helps.

- Gowtham

On Sun, Aug 16, 2015 at 12:24 PM, John <da_audiophile@yahoo.com> wrote:

>
>
>
>
> ----- Original Message -----
> > From: Eric Cook <llua@gmx.com>
> > To: zsh-users@zsh.org
> > Cc: da_audiophile@yahoo.com
> > Sent: Sunday, August 16, 2015 2:44 AM
> > Subject: Re: Errors with my youtube-dl function in ~/.zshrc but I am
> unsure why
> >
> > On 08/16/2015 02:32 AM, John wrote:
> >>  Why does zsh complain about no matches when I invoke my yt function
> and how
> > can I correct the code?  Thanks!
> >>
> >>  From ~/.zshrc:
> >>   yt() { [[ -z "$1" ]] || noglob youtube-dl -q "$1"
> > &; }
> >>
> >>  Output of command:
> >>   % yt https://www.youtube.com/watch?v=OC1JiAUr3ZU
> >                           :(
> >>   zsh: no matches found: https://www.youtube.com/watch?v=OC1JiAUr3ZU
> >>
> >>  Please note that I am not subscribed to the ML so please cc me in the
> > reply.
> >>
> > You have to call the function with noglob to prevent zsh from thinking ?
> is a
> > pattern character.
> >
> > so:
> > % noglob yt https://www.youtube.com/watch?v=OC1JiAUr3ZU
> >
>
> Thank you for the reply.  In the past (month ago), this function worked
> as-is calling the command prefixed by noglob as you recommended.  Is there
> any way I can roll it into the function?
>