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Joined 10 months ago
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Cake day: August 23rd, 2023

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  • Fish, no plugins. The POSIX differences are to your advantage when using interactively. Its amazing how much larger expressions you can construct in the repl before you start moving to a proper file. Its like moving from pure mysql or psql to mycli or pgcli.

    When you add it all up, the amount of effort you’ll expend to learn fish are small compared to the amount of effort you’ll save by trying to recreate the UX with plugins and custom scripts.


  • I’m very suspicious of the uses cases for this. If the compiled bash code is unreadable then what’s the point of compiling to bash instead of machine code like normal? It might be nice if you’re using it as your daily shell but if someone sent me “compiled” bash code I wouldn’t touch it. My general philosophy is if your bash script gets too long, move it to python.

    The only example I can think of is for generating massive install.sh



  • Very standard use case for a fold or reduce function with an immutable Map as the accumulator

    val ints = List(1, 2, 2, 3, 3, 3)
    val sum = ints.foldLeft(0)(_ + _) // 14
    val counts = ints.foldLeft(Map.empty[Int, Int])((c, x) => {
      c.updated(x , c.getOrElse(x, 0) + 1)
    })
    

    foldLeft is a classic higher order function. Every functional programming language will have this plus multiple variants of it in their standard library. Newer non-functional programing languages will have it too. Writing implementations of foldLeft and foldRight is standard for learning recursive functions.

    The lambda is applied to the initial value (0 or Map.empty[Int, Int]) and the first item in the list. The return type of the lambda must be the same type as the initial value. It then repeats the processes on the second value in the list, but using the previous result, and so on until theres no more items.

    In the example above, c will change like you’d expect a mutable solution would but its a new Map each time. This might sound inefficient but its not really. Because each Map is immutable it can be optimized to share memory of the past Maps it was constructed from. Thats something you absolutely cannot do if your structures are mutable.