The Quine Language

Quine is a programming language for writing quines, or rather, one specific quine.

Quine is based on a virtual machine that contains a buffer holding the previous token, a main queue which can hold arbitrary tokens, and a standard output stream. The VM is manipulated by these machine language statements:

• 000 - (e) - raise error: dump the contents of the main queue to standard output, followed by 'e' to indicate that an error has occurred.
• 001 - (i) - disable copying of the previous token to the main queue (and indicate success) by writing current token to the main queue.
• 010 - (n) - copy previous and current token to the main queue.
• 011 - (q) - clear the main queue and commence normal operation.
• 100 - (u) - undertake continuous copying of the previous token buffer to the main queue.

There are no other symbols or operators permitted.

White space is significant: there must be none.

The nature of the parser, tokenizer, and the virtual machine architecture mean that for complex reasons it is a syntax error to place the high level tokens in any order other than:

1. q
2. u
3. i
4. n
5. e

The consequence of this is that the only valid program in the language Quine is this:

quine

When executed it provides this output:

quine