The parent comment is saying that if you write the string twice, you can get the... | Hacker News

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		whatshisface on Sept 28, 2020 \| parent \| context \| favorite \| on: Show HN: A SQL database implemented purely in Type... The parent comment is saying that if you write the string twice, you can get the compiler to check #1 and the runtime to use #2.

ricksharp on Sept 28, 2020 [–]

Not exactly (there is no duplication), a string constant in typescript is it's own type:

  const sql = 'SELECT ...';
  type SQL = typeof sql; 
  // type SQL = "SELECT ..."

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