4 ms·

It's good when it gives a name to what you're doing. connection = establish_connection_given_these_conditions(cond1, cond2) Vs the many lines of checking, cre

It's good when it gives a name to what you're doing. connection = establish_connection_given_these_conditions(cond1, cond2) Vs the many lines of checking, creating the ConnectionFactory, passing in the the conditions to the ConnectionConditionFactory, and generally having a new statement every time you want to blow your nose. What were we doing again? I dunno. I've used it. I'll defend it. It's better than comments when done properly as above.

vog 10y ago
Indeed! More generally, functions are not only about abstraction, but also about decomposition. The only thing that may hurt readability is when the decomposition itself is too much nested. Usually, it's best to split a large task purely linearly in subtasks (functions), and have them called all from a single function. That main task function gives you not only an overview of all sub tasks, but also about the dataflow between them. In constrast, too much subtask nesting (subtasks of subtasks of subtasks) often hide the overall flow, which then makes it hard to get the overall view.
friendzis 10y ago
Code maintenance is hard, therefore a bugfix could easily turn the function to establish_connection_given_these_conditions_and_implicit_one(cond1, cond2); Now the identifier is misleading and becomes a landmine waiting to blow your feet off :( Having done some debugging where identifiers/comments/structure are misleading I am a bit afraid of such code. I am really not sure what is the best way to structure highly imperative code though, because every option I have seen contains some dark corners.
- patmcguire 10y ago
  Fair. On of the good aspects is that it makes this chunk testable, rather than having to test the behavior of the long line of statements. If there's a test for it it's a lot harder to sneak in an implicit assumption.
  - friendzis 10y ago
    What I meant was that the implicit condition may be too context specific, dunno, maybe some NIC flags or something that are extremely unlikely to be caught by tests (especially written by anyone working on the code piece), code reviews or any such measure. Because the code works seemingly well until underlying conditions stop being satisfied. Such conditions happen all the time, but are unproportionaly painful to debug in bulldozer code :( Rant: Even though tests are nearly invaluable, though I personally believe that tests written by the same person writing implementation give a bit false sense of security. I see spec, tests and implementation different representations of author's understanding of the problem. If any two of those (e.g. tests and implementation) are produced from the same mind/understanding then they cannot be used to verify that understanding behind each other is the same.
barrkel 10y ago
What's the difference between cond1 and cond2 parameters? Can they be swapped? If cond1 and cond2 are booleans, they're almost indecipherable at the call site. Why not cond1 && cond2 (or symbolic equivalent)? Abstracting away the gruntwork of your connection factory and your connection condition factory into a couple of separate routines - those are resuable bits of code, they'll let you write this code at a higher level of abstraction using reusable abstractions. But pushing the ugly wiring into a non-reusable black box and pretending it's better design - bullshit.
- patmcguire 10y ago
  Good point on the conditions. I wanted to avoid pasting prod code I'd been working on and was trying to make an example: I generally use this for things like logging. It's best when: 1) The logic is very specific to the situation and isn't reusable 2) Isn't important to the function's api contract.

vog 10y ago

Indeed! More generally, functions are not only about abstraction, but also about decomposition. The only thing that may hurt readability is when the decomposition itself is too much nested. Usually, it's best to split a large task purely linearly in subtasks (functions), and have them called all from a single function. That main task function gives you not only an overview of all sub tasks, but also about the dataflow between them. In constrast, too much subtask nesting (subtasks of subtasks of subtasks) often hide the overall flow, which then makes it hard to get the overall view.

friendzis 10y ago

Code maintenance is hard, therefore a bugfix could easily turn the function to establish_connection_given_these_conditions_and_implicit_one(cond1, cond2); Now the identifier is misleading and becomes a landmine waiting to blow your feet off :( Having done some debugging where identifiers/comments/structure are misleading I am a bit afraid of such code. I am really not sure what is the best way to structure highly imperative code though, because every option I have seen contains some dark corners.

patmcguire 10y ago
Fair. On of the good aspects is that it makes this chunk testable, rather than having to test the behavior of the long line of statements. If there's a test for it it's a lot harder to sneak in an implicit assumption.
- friendzis 10y ago
  What I meant was that the implicit condition may be too context specific, dunno, maybe some NIC flags or something that are extremely unlikely to be caught by tests (especially written by anyone working on the code piece), code reviews or any such measure. Because the code works seemingly well until underlying conditions stop being satisfied. Such conditions happen all the time, but are unproportionaly painful to debug in bulldozer code :( Rant: Even though tests are nearly invaluable, though I personally believe that tests written by the same person writing implementation give a bit false sense of security. I see spec, tests and implementation different representations of author's understanding of the problem. If any two of those (e.g. tests and implementation) are produced from the same mind/understanding then they cannot be used to verify that understanding behind each other is the same.

barrkel 10y ago

What's the difference between cond1 and cond2 parameters? Can they be swapped? If cond1 and cond2 are booleans, they're almost indecipherable at the call site. Why not cond1 && cond2 (or symbolic equivalent)? Abstracting away the gruntwork of your connection factory and your connection condition factory into a couple of separate routines - those are resuable bits of code, they'll let you write this code at a higher level of abstraction using reusable abstractions. But pushing the ugly wiring into a non-reusable black box and pretending it's better design - bullshit.

patmcguire 10y ago
Good point on the conditions. I wanted to avoid pasting prod code I'd been working on and was trying to make an example: I generally use this for things like logging. It's best when: 1) The logic is very specific to the situation and isn't reusable 2) Isn't important to the function's api contract.