model to model function calling?

[eluser]delay[/eluser]
I have a general_model in which I keep various string and date manipulation functions. I want to call the general_model functions within other models.

For instance I have a search_model and it returns search results. One general function I use limits the description text to a few words, I keep this function in my general_model since its useful in other areas as well.

I haven't figured the syntax for calling on one model from another model. Is this doable? If not, what is the correct way to handle what I want to do?

Thanks for any help.