Comment by CraigJPerry | Hacker News Reader

Comment by CraigJPerry | Hacker News Reader

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What would be a good example of the kinds of things a 100 line function would be doing?

I don't see that in my world so i'm naively trying to inline functions in codebases i'm familiar with and not really valuing the result i can dream up.

For one, my tests would be quite annoying, large and with too much setup for my taste. But i don't think i'd like to have to scroll a function, especially if i had to make changes to the start and end of the function in one commit.

I'm curious of the kinds of "long script" flavoured procedures, what are they doing typically?

I ask because some of the other stuff you mentioned i really strongly agree with like "Focus on separating pure code from stateful code" - this is such an under valued concept, and it's an absolute game changer for building robust software. Can i extract a pure function for this and separately have function to coordinate side effects - but that's incompatible with too long functions, those side effectfull functions would be so hard to test.

> What would be a good example of the kinds of things a 100 line function would be doing?

If you have a shopping list with 100 items, that does not mean the complexity of that is high.

Longer functions are worse, everything else being equal, but sometimes they have very low complexity.

To answer your question: if you have, for example, a function that returns for a key a certain value (basically a dictionary) for example for some translations that can be a very long function. Of course you could take the data out of the code into a data file, etc. but there is nothing wrong on principle about a function like that. A function like that is closer to extract state into data than one where that gets refactored into many small functions.

> What would be a good example of the kinds of things a 100 line function would be doing?

For me i see it alto in older video game engines with a switch statement that has 100s of possible states that need to be taken into account.

That kind of code is less common these days but its nice to be able to see all the possible states in a single switch statements vs them all being abstracted away in multiple classes that handle a subset of each state transition.

This is one case where having a super long function makes readability far better than abstracting away the states into multiple classes that all need to be read to understand the state of the world.

Containing the giant switch statement in a byte code interpreter or a tokeniser.

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