[Haskell-cafe] Memory leak in infinite recursion

[Dr.Koster]

In general infinite monadic recursion will leak, since the tail position is always >> or >>= instead of your own recursive function, but under certain situations, e.g. IO without arguments, the compiler will figure there's no need to push new stack frame. But anyway it's better to checkout yourself rather relying on some weak assumptions.


发自我的iPhone

------------------ Original ------------------
From: Никита Фуфаев <kitttoran at gmail.com>
Date: Wed,Jun 20,2018 2:37 AM
To: haskell-cafe <haskell-cafe at haskell.org>
Subject: Re: [Haskell-cafe] Memory leak in infinite recursion



Hello everyone


In C you can't implement main loop with recursion like
void mainLoop() {
  doSomething();
  mainLoop();
}  
because without optimisations stack will overflow.
In haskell it's common to write
mainLoop = doSomething >> mainLoop, and it doesn't leak memory because of haskell's evaluation model.
Does memory leak or argument stack overflow happen in this case?
mainLoop = doSomething >> mainLoop >> exit ExitSuccess
What about this case?
mainLoopModeA = do
  doSomething
  when condition mainLoopModeB
  mainLoopModeA
mainLoopModeB = do
  doSomethingElse
  when anotherCondition mainLoopModeA
  mainLoopModeB

or this case?
mainLoopModeA = do
  doSomething
  if condition
    then mainLoopModeB
    else mainLoopModeA
mainLoopModeB = do
  doSomethingElse
  if anotherCondition 
    then mainLoopModeA
    else mainLoopModeB


-- 
Nikita Fufaev
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.haskell.org/pipermail/haskell-cafe/attachments/20180620/dda33fc3/attachment.html>