Self-taps are legal, and nothing holds one passive #100

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opened 2026-09-24 12:49:58 +00:00 by bcox · 0 comments

bcox commented

2026-09-24 12:49:58 +00:00

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A slot pointed at itself -- a string's bridge_tap or return_tap, a board's strings_tap, strings_mask or input_tap, any engine's input tap -- is a loop nothing holds passive. The passive-bridge branch's final review reported that a string bridged to its own slot and a board whose strings are its own slot both run to the rail, as an input_tap self-tap already can on main. A throwaway probe in dsp/bridge_test.cc's bench measured the board fed its own send at R 1, kicked once with 0.1 and one unit of load, holding a peak of 0.00748 every second from 1 s to 10 s without decaying; the string bridged to itself at loss gain 0.9999 decayed to exact zero within a second.

The editor's tooltips say a bridge between a string and a board is stable at any coupling and a slot pointed at itself is not. The question is where the refusal belongs: the editor, the format's reader, or the engine reading a self-tap as kNoTap.

See docs/superpowers/ledgers/2026-09-23-passive-bridge-ledger.md, Follow-ups.

A slot pointed at itself -- a string's `bridge_tap` or `return_tap`, a board's `strings_tap`, `strings_mask` or `input_tap`, any engine's input tap -- is a loop nothing holds passive. The passive-bridge branch's final review reported that a string bridged to its own slot and a board whose strings are its own slot both run to the rail, as an `input_tap` self-tap already can on `main`. A throwaway probe in `dsp/bridge_test.cc`'s bench measured the board fed its own send at R 1, kicked once with 0.1 and one unit of load, holding a peak of 0.00748 every second from 1 s to 10 s without decaying; the string bridged to itself at loss gain 0.9999 decayed to exact zero within a second. The editor's tooltips say a bridge between a string and a board is stable at any coupling and a slot pointed at itself is not. The question is where the refusal belongs: the editor, the format's reader, or the engine reading a self-tap as `kNoTap`. See `docs/superpowers/ledgers/2026-09-23-passive-bridge-ledger.md`, Follow-ups.