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Parsing Expression Grammar vs. regexes: Building Org parser in Lisp that exports to HTML (via SXML)

Demonstrates PEG over regex for building an Org parser that outputs HTML via SXML.

Steady
Signal score
18
as of 20h ago
Trajectory
↓ Cooling
7-day est. ~0

Why this scored 18

every term, weighted
Velocity+0.0 / 40

Engagement gained per hour since the last capture, against the fastest item on its own source

Acceleration+9.7 / 25

Whether that velocity is itself speeding up, as a per-hour rate

Cross-source spread+0.0 / 25

How many independent communities are talking about the same entity

Recency+9.1 / 10

Decays to zero over 14 days

Saturation penalty−0.8 / 30

Subtracted once something is big and old — we rank what's next, not what's peaked

Composite18.0

Weights are hand-tuned, not learned — we're calibrating them against realized trends as history accumulates. On a topic's first sighting there's no previous reading to compare against, so acceleration starts from a neutral prior rather than a measurement, and velocity falls back to engagement over its whole lifetime until a second reading exists. Full methodology

Outlook

low confidence · estimate, not a guarantee

7-day

~0

range 0–12

14-day

~0

range 0–14

30-day

~0

range 0–19

Signal history

7-day window (free)
075

projected trajectory (estimate, not a guarantee)

Entities

lisp
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Drop this in a README or blog post — it updates automatically as the score moves.