[Haskell-cafe] GHC predictability

[Don Stewart]

andrewcoppin:
> Darrin Thompson wrote:
> >These "tricks" going into Real World Haskell?
> 
> Seconded.
> 
> >When you say someone
> >needs to get familiar with the "STG paper" it scares me (a beginner)
> >off a little, an I've been making an effort to approach the papers.
> 
> Well, I'm the sort of contrary person who reads random papers like that 
> just for the fun of it. But when somebody says something like this, I 
> don't think "ooo, that's scary", I think "ooo, somebody really ought to 
> sit down and write a more gentle introduction". You really shouldn't 
> *need* to know the exact implementation details to get some idea of what 
> will perform well and what won't. But obviously you do need some kind of 
> high-level understanding of what's going on. The STG paper isn't a good 
> way to get that high-level overview.

Andrew, would you say you understand the original problem of why

    mean xs = sum xs / fromIntegral (length xs)

was a bad idea now? Or why the left folds were a better solution?

-- Don