Can 1/3 and 1/3 = 2/6? It seemed so

Re:Can 1/3 and 1/3 = 2/6? It seemed so by bradlys on Tuesday May 26, 2020 @11:05AM (#23312054)

Interesting - I never thought of CS as being something to help with this. Instead, I’d think of other engineering fields where there is a heavy reliance on correct units and unit conversion. Pound of feathers vs pound of gold , etc...

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Re:Can 1/3 and 1/3 = 2/6? It seemed so by scarmig on Tuesday May 26, 2020 @11:35AM (#23312439)

F# offers a nifty "unit of measure" language feature to help with that. You might have

  [<Measure>] type lbFeather 
  [<Measure>] type lbGold
  [<Measure>] type lbLead

  let convertGoldToLead ( weight : float<lbGold> ) = 1.0<lbLead> / 1.0<lbGold> * weight

  // works
  let barOfGold = 1.0<lbGold>
  let barOfLead = convertGoldToLead barOfGold
  // doesn't work
  let bagOfFeathers = 1.0<lbFeather>
  let leadDuck = convertGoldToLead bagOfFeathers
  // Error reported: mismatched units.

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