why isn't inline on tailrec functions supported? I...
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TwoClocks
09/09/2020, 1:15 AMwhy isn't inline on tailrec functions supported? It seems like a kinda obvious thing to add, as if you want to be more FP you'd use more tailrec fun's than while() loops.
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Nir
09/09/2020, 1:29 AMI realize it's a bit of a non-answer but for me the more surprising part is that kotlin supports tailrec to start with
Nir
09/09/2020, 1:30 AMclojure doesn't even support tail recursion. It's just not a terribly useful feature unless your language wants to do everything to avoid loops for some reason (like scheme for educational/simplicity reasons), or if your language is so heavy on purity that you don't want to mutate the local variable for a loop
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TwoClocks
09/09/2020, 2:29 AMtailrec = while loop to the compiler... which is already inlined.
TwoClocks
09/09/2020, 2:30 AM@Nir it's in scala... so there is JVM code to steal 🙂
TwoClocks
09/09/2020, 2:33 AM@Ruckus So you think while() loops arn't inlined? Every while() loop is a function call?
TwoClocks
09/09/2020, 2:33 AMa tailrec function and a while() loop are equivalent, by definition.
TwoClocks
09/09/2020, 2:35 AMwhat am I missing? inline = skip the call, copy'n paste this code into everyplace that calls it.
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Ruckus
09/09/2020, 2:39 AMI shall delete my comments to hide my shame from the world.
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TwoClocks
09/09/2020, 2:39 AM@Nir I prefer tailrec to while() except for the trivial case. no `var`s easier for the compiler to figure out there are no side effects. should result if faster code (but I've never actually tested). maybe just a story I tell myself.
TwoClocks
09/09/2020, 2:39 AM@Ruckus no worries 🙂 I get confused between unrolls and inline sometimes.
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Nir
09/09/2020, 3:29 AMSeems unlikely it results in faster code, but I don't know the JVM well
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Jakub Pi
09/09/2020, 6:26 AM@Nir Clojure had support for tail recursion 3 years ago, there's just no explicit key word for it. Same usage patterns apply - has to be the last statement etc...
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Jakub Pi
09/09/2020, 6:28 AMIt also has trampoline as part of the standard library
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nanodeath
09/09/2020, 3:29 PMit looks like they just haven't gotten around to it yet https://youtrack.jetbrains.com/issue/KT-27897
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TwoClocks
09/09/2020, 6:29 PM@Jakub Pi I've never heard of trampoline before this. that's a neat idea. thanks!
TwoClocks
09/09/2020, 6:32 PM@nanodeath a 4 year old ticket w/ not planned implementation doesn't sound too hopeful for "getting around to it". But at least they are aware of it, which is better than nothing.
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nanodeath
09/09/2020, 6:44 PMat least it's not closed 😛
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