Facts:
Their implementations share little more than the standard C library and perhaps some RegExp code. Even though they are addressing the same problems, and solving the same details, to a very large extent.
Sigh.
Twenty five years ago, every computer hardware vendor has its own proprietary OS. Then came UNIX - and the general reaction was: who on earth would want a general OS which runs on different types of hardware?
Here I am - one weak voice in the desert - saying that we need a generic Scripting Kernel. Neither the Tcl nor the Python people seem to care. A common reaction is: sure, it's a good idea, but it will never happen - the affected parties have no reason to relinquish control of what they each have laboriously and successfully been perfecting over the years.
There's a lot more to say about this...
User comments:
Sapphire, a (short term?)project to test the ability to re-create perl with standard libs, seems to be a step towards this concept.
http://www.perl.com/pub/2000/09/sapphire.html
A modal scripting language might be cool where you can change the way the interpreter looks at the code. This would allow you to write the way you like to, and switch over to more convienient style when doing certain tasks like GUI interaction.