Tail call elimination

[BCS]

Reply to Nick,

> "bearophile" <bearophileHUGS at lycos.com> wrote in message
> news:ggmm4n$o6d$1 at digitalmars.com...
> 
>> - I know it's not necessary, just as closures aren't necessary in an
>> OO
>> language,
>> because you can create a class every time you may want a closure. But
>> functional
>> programmers are used to use certain idioms, such idioms they are part
>> of
>> the
>> functional style of mind (and they are useful because you can build
>> over
>> them.
>> Functional programming is all about building functions using other
>> functions). If
>> you want to push some functional-style in D (and I think it's a good
>> thing) then
>> several things are necessary (quite useful) to allow such style of
>> mind
>> (even if
>> some of them may look redundant to nonfunctional programmer, like
>> closures).
>> This is why I think things tail call elimination and a little may be
>> useful if D wants
>> to become more functional.
> Maybe I'm just too new to functional programming and tail call
> elimination, but I don't see how TCE could be needed for a functional
> frame of mind. It's just an optimization, right? And as I understand
> it, it just decreases performance hits from function call overhead and
> prevents the call stack from growing proportionally to the depth of
> recursion (or more simply, it just keeps the size of the call stack
> down). Can you provide an example situation where a lack of TCE would
> be a problem for a functional programmer?
> 

Some not exactly function programs (Lisp programs that accept user input) 
have infinite recursion. Without TCE they will always crash sooner or later, 
with it they run just fine.