Visualizing Garbage Collection Algorithms
Great dataviz with animated GIFs
(tags: algorithms gc memory visualization garbage-collection dataviz refcounting mark-and-sweep)
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John Gruber’s canonical description of Markdown’s syntax does not specify the syntax unambiguously. In the absence of a spec, early implementers consulted the original Markdown.pl code to resolve these ambiguities. But Markdown.pl was quite buggy, and gave manifestly bad results in many cases, so it was not a satisfactory replacement for a spec. Because there is no unambiguous spec, implementations have diverged considerably. As a result, users are often surprised to find that a document that renders one way on one system (say, a GitHub wiki) renders differently on another (say, converting to docbook using Pandoc). To make matters worse, because nothing in Markdown counts as a “syntax error,” the divergence often isn’t discovered right away. There’s no standard test suite for Markdown; the unofficial MDTest is the closest thing we have. The only way to resolve Markdown ambiguities and inconsistencies is Babelmark, which compares the output of 20+ implementations of Markdown against each other to see if a consensus emerges. We propose a standard, unambiguous syntax specification for Markdown, along with a suite of comprehensive tests to validate Markdown implementations against this specification. We believe this is necessary, even essential, for the future of Markdown.
Postcodes at last but random numbers don’t address efficiency
Karlin Lillington assembles a fine collection of quotes from various sources panning the new Eircode system:
Critics say the opportunity has been missed to use Ireland’s clean-slate status to produce a technologically innovative postcode system that would be at the cutting edge globally; similar to the competitive leap that was provided when the State switched to a digital phone network in the 1980s, well ahead of most of the world. Instead, say organisations such as the Freight Transport Association of Ireland (FTAI), the proposed seven-digit format of scrambled letters and numbers is almost useless for a business sector that should most benefit from a proper postcode system: transport and delivery companies, from international giants like FedEx and UPS down to local courier, delivery and service supplier firms. Because each postcode will reveal the exact address of a home or business, privacy advocates are concerned that online use of postcodes could link many types of internet activity, including potentially sensitive online searches, to a specific household or business.
(tags: eircode government fail ireland postcodes location ftai random)