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Parsing Expression Grammar vs. Regexes: Building Org Parser in Lisp, Export HTML

Compares PEG and regexes for building an Org parser in Lisp, useful for custom parsing tasks.

Steady
Signal score
16
as of 1d ago
Trajectory
↓ Cooling
7-day est. ~0

Why this scored 16

every term, weighted
Velocity+0.0 / 40

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

Acceleration+11.3 / 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+7.9 / 10

Decays to zero over 14 days

Saturation penalty−2.7 / 30

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

Composite16.5

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)
021

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.