A collection of Bad Code Smells in a Catalog form for Developers & Researchers. Code Smell is a typical bad code implementation, and learning these concepts immiedietly makes you a better developer!
  • spartanatreyu ( spartanatreyu@programming.dev ) 
    9·
    2 years ago

    This doesn’t seem overly useful.

    It’s a list taken out of a bunch of books with no regard for how something can be the best path in one language and a smell in another language.

    Look at this page for example: https://luzkan.github.io/smells/imperative-loops

    It suggests using functional loop methods (.map(), .reduce(), .filter()) instead of using imperative loops (for, for in, for each) but completely disregards the facts that imperative loops also have access to the break, continue, and return keywords to improve performance.

    For example: If I have an unsorted list of 1000 cars which includes a whole bunch of information per car (e.g. color, year manufactured, etc…), and I want to know if there were any cars were manufactured before the year 1980, I can run an imperative loop through the list and early return true if I find one, and only returning false if I haven’t found one by the end of the list.

    If the third car was made in 1977, then I have only iterated through 3 cars to find my answer.

    But if I were to try this with only functional loops, I would have to iterate through all 1000 cars before I had my answer.

    A website with blind rules like this is going to lead to worse code.

      • sik0fewl ( sik0fewl@lemmy.ca ) 
        3·
        2 years ago

        Ya, streams may seem tedious (why do I have to call stream and collect?), but it’s like that for performance (and probably backwards compatibility).

        If writing readable code is not peformant, then the language implementation needs to be fixed.

          • mbtrhcs ( mbtrhcs@feddit.org ) 
            2·
            2 years ago

            Yeah, in Java calling first() on a stream is the same as an early return in a for-loop, where for each element all of the previous stream operations are applied first.

            So the stream operation

            cars.stream()
    .filter(c -> c.year() < 1977)
    .first()

            is equivalent to doing the following imperatively

            for (var car : cars) {
    if (car.year() < 1977) return car;
}

            Not to mention Kotlin actually supports non-local returns in lambdas under specific circumstances, which allows for even more circumstances to be expressed with functional chaining.

            • nous ( nous@programming.dev ) English
              3·
              2 years ago

              These are not quite equivalent. In terms of short-circuiting yeah they both short-circuit when they get the value. But the latter is returning from the current function and the former is not. If you add a return to that first example then they are equivalent. But then cannot be used in line. Which is a nice advantage to the former - it can be used inline with less faff as you can just assign the return to a value. The latter needs you to declare a variable, assign it and break from the loop in the if.

              Personally I quite like how the former requires less modification to work in different contexts and find it nicer to read. Though not all logic is easier to read with a stream, sometimes a good old for loop makes the code more readable. Use which ever helps you best at each point. Never blindly apply some pattern to every situation.

  • Kissaki ( Kissaki@programming.dev ) English
    6·
    2 years ago

    The items don’t seem concise and always clear. But seems like a good, inspiring resource for things to consider.

    If it is expected that a method might fail, then it should fail, either by throwing an Exception or, if not - it should return a special case None/Null type object of the desired class (following the Null Object Pattern), not null itself.

    I’ve never heard of evading null with a Null object. Seems like a bad idea to me. Maybe it could work in some language, but generally I would say prefer result typing. Introducing a result type wrapping or extending the result value type is complexity I would be very evasive to introduce if the language doesn’t already support result wrapper/state types.

      • Kissaki ( Kissaki@programming.dev ) English
        3·
        2 years ago

        with this in mind

        With what in mind? Evading NULL?

        Languages that make use of references rather than pointers don’t have this Dualism. C# has nullable references and nullability analysis, and null as a keyword.

        What does your reasoning mean in that context?

      • AbelianGrape ( AbelianGrape@beehaw.org ) 
        2·
        2 years ago

        “Monadic type” has something like three meanings depending on context, and it’s not clear which one you mean. One of them is common in math, but not so common in programming, so probably not that. But neither “parametric types with a single argument” nor “types that encode a category-theoretic monad” have the property you say, as far as I know.

        I imagine you’re probably referring to the latter, since the optional monad exists. That’s very different from returning null. The inhabitants of Integer in Java, for example, are the boxed machine ints and null. The inhabitants of Optional[Integer] (it won’t let me use angle brackets here) are Optional.of(i) for each machine int i, Optional.empty(), and null.

        Optional.empty() is not null and should not be called a “Null object.” It’s also not of type Integer, so you’re not even allowed to return it unless the function type explicitly says so. Writing such function types is pretty uncommon to do in java programs but it’s more normal in kotlin. In languages like Haskell, which don’t have null at all, this is idiomatic.