So what is the convention to quickly compile and run your code?

Actually, I'm not sure what you're asking for. Textastic allows you to edit files in those languages with support for syntax highlighting but you can't run the code on an iPad due to Apple's restrictions. You would have to upload them to a computer (for example using SFTP) and run it there.

Thank you for the quick feedback.  Tell me if this sounds silly: Write/edit code on Textastic, save the file on the cloud, switch to an SSH app, pull up the file just saved, and compile/run at the command line.  I realize it would be much simpler to just use a laptop, but I'd really like to know if the iPad can operate as a de facto laptop for simple programming use on the go.  (Either way, I'm buying Textastic the day I get my iPad.  It looks super awesome.)  

Well, yes, what you described is probably the way to go.

Awesome.  Thanks again for your fast replies.  You will soon count me as a customer.  : ) 

Would you be able to build into textastic ideone's API?
http://ideone.com/api

This would make textastic stellar. :-)

I've mentioned ideone is this topic: http://feedback.textasticapp.com/topic/7730-remote-source-code-compilation/