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11747 :: What Araq thinks about HappyX?

• Qtless (orginal) [2024-06-11T16:35:18+02:00] view original

  I would like to know what the creator of Nim thinks about HappyX

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• Araq (orginal) [2024-06-11T18:00:45+02:00] view original

  I have not yet read this codebase, sorry. But I know people who are not affiliated to the project and are about to use it in production.

  PS: Stop using regexes for parsing.

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• moigagoo (orginal) [2024-06-11T19:00:32+02:00] view original

  I'm loving this trend :-)

  Let's start a monthly "What Araq thinks about X" blog series?

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• Clonk (orginal) [2024-06-12T13:43:39+02:00] view original

  Hijacking @moigagoo 's joke suggestion to ask if we could have the monthly (or once every 2/3 month if that is too oftem) Nim meet-up online back.

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• alexeypetrushin (orginal) [2024-06-13T03:22:23+02:00] view original

  @Araq can you please explain about regex? Why it's bad and what's the better way? And, maybe link to some code, simple to understand parser with the better approach?

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• dwhall256 (orginal) [2024-06-13T15:13:28+02:00] view original

  Instead of a meet-up; how about a community code roast. Once a month, someone (the host/author) nominates a project they want help improving. The community all pitches in on ideas to make it better; it could be a quick write-up or a thorough PR.

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• Qtless (orginal) [2024-06-13T17:22:25+02:00] view original

  sounds really good!

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• Araq (orginal) [2024-06-14T12:05:56+02:00] view original

  The lexing step is usually sufficiently described by a list of (pattern, action) pairs (maybe with priorization)

  re"if\b": keywordIf
  re"[A-Za-z_]+[A-Za-z_0-9]*": identifier
  re"\d+": number
  
  Run

  So it's not the regexes per se that are the problem. The problem comes from the fact that the typical regex library has no support for this setup at all and instead makes you write if|[A-Za-z_]+[A-Za-z_0-9]*|\d+ with no support to distinguish between the different cases.

  A different but related problem is that regexes are not used only for the lexing step but also to directly extract data and skipping the parsing step which is terrible for correctness.

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