basic_pattern_matcher

A basic pattern matcher for Rust using . as a delimiter, * for single level wildcard, ** for multi level wildcard.

This uses a trie-based architecture, and can probably be further optimized (see https://bravenewgeek.com/fast-topic-matching/ which finds that tries actually scale better)

Largely written by Gemini 2.5 Pro

Concurrency

This does not support concurrency out of the box. For concurrent (thread safe) applications, some ideas to try would be:

• Using an actor thread, and handling small batches of requests from a channel (loop and grab what ever is available, up to N, then respond)
• Use Arc (simpler, potentially more overhead than actor model)

cargo add basic_pattern_matcher

M3 Max 128GB:

--- Adding Patterns ---
Added pattern: stock.nyse.*.price             ID: 101 Time: 18.834µs
Added pattern: stock.**.price                 ID: 101 Time: 1.125µs
Added pattern: stock.nasdaq.aapl.price        ID: 102 Time: 875ns
Added pattern: stock.*.ibm.price              ID: 103 Time: 834ns
Added pattern: stock.nyse.**                  ID: 104 Time: 5.291µs
Added pattern: stock.**                       ID: 105 Time: 375ns
Added pattern: finance.#                      ID: 106 Time: 500ns
Added pattern: *.nyse.ibm.*                   ID: 107 Time: 708ns
Added pattern: **.price                       ID: 108 Time: 709ns
Added pattern: stock.nyse.ibm.volume          ID: 109 Time: 792ns
--- Matching Topics ---
Topic: stock.nyse.ibm.price           Matches: [("stock.nyse.*.price", 101), ("stock.*.ibm.price", 103), ("stock.**.price", 101), ("stock.nyse.**", 104), ("*.nyse.ibm.*", 107), ("stock.**", 105), ("**.price", 108)]  Time: 13.917µs
Topic: stock.nasdaq.aapl.price        Matches: [("**.price", 108), ("stock.nasdaq.aapl.price", 102), ("stock.**.price", 101), ("stock.**", 105)]  Time: 1.417µs
Topic: stock.nyse.msft.price          Matches: [("**.price", 108), ("stock.nyse.*.price", 101), ("stock.**", 105), ("stock.**.price", 101), ("stock.nyse.**", 104)]  Time: 1.292µs
Topic: stock.nyse.ibm.volume          Matches: [("stock.**.price", 101), ("*.nyse.ibm.*", 107), ("stock.**", 105), ("stock.nyse.**", 104), ("stock.nyse.ibm.volume", 109), ("**.price", 108)]  Time: 4.458µs
Topic: stock.foo.bar.baz.qux          Matches: [("stock.**.price", 101), ("stock.**", 105), ("**.price", 108)]  Time: 1.083µs
Topic: finance.load                   Matches: [("**.price", 108)]  Time: 583ns
Topic: other.nyse.ibm.price           Matches: [("**.price", 108), ("*.nyse.ibm.*", 107)]  Time: 666ns
Topic: something.completely.different Matches: [("**.price", 108)]  Time: 542ns
Topic: stock.price                    Matches: [("**.price", 108), ("stock.**", 105), ("stock.**.price", 101)]  Time: 833ns
Topic: stock.nyse.goog.data           Matches: [("**.price", 108), ("stock.**", 105), ("stock.**.price", 101), ("stock.nyse.**", 104)]  Time: 2.458µs