tutorial · HACKER NEWS RECOMMENDATION
Depth-first search in APL
Dyalog · 2 HN recommenders · 3 recommendation months
Recommended by 2 Hacker News commenters across 3 months (2019–2021).
SignalTube analysis
Among 10 other tutorial videos tagged Functional programming, the mean is 3.7 distinct HN recommenders. This video has 2 distinct HN recommenders, below that mean. Recommendations span 3 distinct months; the peer average is 3.5 months. This is a data-derived comparison, not a human review or quality rating.
60% of its 5 labeled comments are marked as recommendations or strong recommendations. HN mention years are 2019–2021; those years describe discussion history, not upload date. Its verified runtime is 11 minutes 32 seconds. YouTube lists its publication date as 2014-07-18.
- Channel / speaker
- Dyalog
- Verified runtime
- 11m 32s
- YouTube upload date
- 2014-07-18
- Hacker News mention years
- 2019–2021
SAME TOPIC AND FORMAT
Compare with related videos
The comparison cohort uses other tutorial videos in Functional programming. “Shared recommenders” counts HN users who recommended both videos in the source graph.
| Video | HN recommenders | Recommendation months | Positive label share | Shared recommenders | Runtime | Upload date |
|---|---|---|---|---|---|---|
| Depth-first search in APLCurrent video | 2 | 3 | 60% | — | 11m 32s | 2014-07-18 |
| Emacs Rocks! Episode 14: Paredittutorial · emacsrocks | 8 | 7 | 89% | No recorded overlap | 3m 25s | 2013-03-21 |
| Build a real-time Twitter clone in 15 minutes with LiveView and Phoenix 1.5tutorial · Chris McCord | 7 | 6 | 62% | No recorded overlap | 17m 55s | 2020-04-22 |
| David Beazley - Lambda Calculus from the Ground Up - PyCon 2019tutorial · PyCon 2019 | 4 | 4 | 100% | No recorded overlap | 206m 34s | 2019-05-02 |
THREE SOURCE-BASED CONTEXT POINTS
Why Hacker News recommends it
Each note combines the dataset’s stance label and short rationale; comment bodies are not reproduced. Open the HN source for the original discussion.
The archive classifies this as a strong recommendation in “Show HN: KatLang – Language for Calculations”. Its short rationale: Beautiful presentation on higher-order functions for reusable depth-first search; should be seen.
The archive classifies this as a contextual reference in “Bryan Cantrill interviews Arthur Whitney (2009)”. Its short rationale: Cited as John Scholes's approach to tree representation with index vectors.
The archive classifies this as a strong recommendation in “J can look like APL or English”. Its short rationale: Brilliant step-by-step APL depth-first search narration by John Scholes.