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User:Rainwave/Drafts/HashTag
- The title of this article is not correct because of technical limitations. The correct title is actually #Tag.
- This is still a work in progress. It may be changed in the future.
#Tag is an esoteric programming language created by User:Rainwave in 2026. It can be thought of as a hybrid of 1-tag and 2-tag systems, or a modification of 1-tag system that conditionally deletes two symbols if the first symbol in the queue is the special symbol #.
Semantics
Like 1-tag system, the language operates on a queue of symbols. Each symbol in the alphabet has a corresponding production string .
At each step, the first symbol in the queue is read and one of the following actions is performed:
- If the symbol is a
#, delete the first two symbols in the queue. - Otherwise, append the production string of the first symbol to the end of the queue and then delete the first symbol in the queue.
Computational class
#Tag is Turing complete as it can simulate The Waterfall Model.