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I've long been a zero-based-index-loving geek, but I'm now coming around to preferring one-based indices in programming. Hopefully in the near future I'll writ

by domador 11y ago

I've long been a zero-based-index-loving geek, but I'm now coming around to preferring one-based indices in programming. Hopefully in the near future I'll write a blog post detailing why. Regarding the article itself... sorry, Dijkstra, but I think conventions C and D are more beautiful, as I prefer discrete ranges where the signs on both ends are the same. Convention C is my favorite, as it only makes mention of members of the range, not numbers that lie outside of it.

learnstats2 11y ago
Reading Dijkstra's own argument convinced me that 1-indexing is better. Convention C (consistently non-strict) is the one that we normally use to describe ranges in English.
- baddox 11y ago
  While the article is explicitly only dealing with natural numbers, convention C is insufficiently expressive for anything more granular than the natural numbers.
eblume 11y ago
I have an example of a similar journey I followed. The Lua language has a 1-based indexing scheme. Furthermore, the only thing that differentiates a hash-map from an ordered array is the existence of only keys in the range [1, ∞) (and they must be entirely contiguous starting from 1 until the last present key). The interface for arrays and hash-map data types is uniform, called a 'table', which has your standard `mapper[key] = value` syntax (and also, equivalently, `mapper.key = value` for well-formatted string-literal keys). This results in the very surprising and confounding fact that if a naive programmer doesn't realize that Lua has this system, they will very likely end up starting from 0 and build an unordered hash map rather than an ordered array - complete with all the resulting performance penalties and unordered traversals. For a long time this struck me as being absolutely absurd and very damning. After working with Lua for a while, though, there began to be a certain elegance to it that I could admire. There is a SO post that goes in to some of the benefits[0][1]. I still much prefer 0-based indexing though. 0: http://stackoverflow.com/questions/2785704/why-do-lua-arraystables-start-at-1-instead-of-0 http://stackoverflow.com/questions/2785704/why-do-lua-arrays... 1: Irony intended.

by domador 11y ago

learnstats2 11y ago

Reading Dijkstra's own argument convinced me that 1-indexing is better. Convention C (consistently non-strict) is the one that we normally use to describe ranges in English.

baddox 11y ago
While the article is explicitly only dealing with natural numbers, convention C is insufficiently expressive for anything more granular than the natural numbers.

eblume 11y ago

I have an example of a similar journey I followed. The Lua language has a 1-based indexing scheme. Furthermore, the only thing that differentiates a hash-map from an ordered array is the existence of only keys in the range [1, ∞) (and they must be entirely contiguous starting from 1 until the last present key). The interface for arrays and hash-map data types is uniform, called a 'table', which has your standard `mapper[key] = value` syntax (and also, equivalently, `mapper.key = value` for well-formatted string-literal keys). This results in the very surprising and confounding fact that if a naive programmer doesn't realize that Lua has this system, they will very likely end up starting from 0 and build an unordered hash map rather than an ordered array - complete with all the resulting performance penalties and unordered traversals. For a long time this struck me as being absolutely absurd and very damning. After working with Lua for a while, though, there began to be a certain elegance to it that I could admire. There is a SO post that goes in to some of the benefits[0][1]. I still much prefer 0-based indexing though. 0: http://stackoverflow.com/questions/2785704/why-do-lua-arraystables-start-at-1-instead-of-0 http://stackoverflow.com/questions/2785704/why-do-lua-arrays... 1: Irony intended.