setting up variables in alias is not working - linux

Question

I want my alias to pick up variables that I pass in commandLine:
For example, startdocker 004 should execute the following
docker run -d -t -p 8080:8080 -v /var/source:/source -P mydockerregistry:5000/foo/bar:004
(004 is the tag I am passing in commandLine).
I tried the following in my .bashrc (sourced after the change).
alias startdocker='function dockerStartTag(){ echo "docker run -d -t -p 8080:8080 -v /var/source:/source -P mydockerregistry:5000/foo/bar: $1";};dockerStartTag'
when I run startdocker 004, It is not picking up 004.
It is empty and hence defaults to "latest" by docker.
what is the correct way to do it? what am I doing wrong?
Thanks
EDIT
I don't want to echo but execute the command.
The correct answer is provided below

Answer 1

There's no reason to put a function inside an alias. Just do
function startdocker(){ echo "docker run -d -t -p 8080:8080 -v /var/source:/source -P mydockerregistry:5000/foo/bar: $1"; }
This now works on my system:
$ startdocker 004
docker run -d -t -p 8080:8080 -v /var/source:/source -P mydockerregistry:5000/foo/bar: 004
And to actually run it, we just need:
function startdocker(){ docker run -d -t -p 8080:8080 -v /var/source:/source -P mydockerregistry:5000/foo/bar: $1; }