Re^2: Tail recursion elimination

There's a very good reason to eliminate tail recursion (in any language): to save memory if the recursion runs deep. Unfortunately, it only works when you have tail recursion.

The other "unfortunately" is that, at least the last time I checked, goto& was slower than recursing.

We're building the house of the future together.

Comment on Re^2: Tail recursion elimination Download Code

Replies are listed 'Best First'.
Re^3: Tail recursion elimination by diotalevi (Canon) on Apr 28, 2006 at 20:10 UTC
You appear to have misunderstood. I didn't say that eliminating recursion was bad, I said that using `goto &{...}` nearly always is. There are probably better ways to do this in perl but one of the "best" ways I know of is to just go back to the top of the routine after setting @_ with the new args. For short routines and such. `sub foo { { ... # Recurse but without actually calling foo() again. @_ = ...; redo; } }` [download] I also expect that there are better ways to save on memory than eliminating stack frames. ⠤⠤ ⠙⠊⠕⠞⠁⠇⠑⠧⠊	[reply] [d/l] [select]
Re^4: Tail recursion elimination by billh (Pilgrim) on Apr 28, 2006 at 20:27 UTC
Fine if the routine is singly recursive, but if you have mutually recursive subroutines, then that won't work. Bill H `perl -e 'print sub { "Hello @{[shift]}!\n" }->("World")'` [download]	[reply] [d/l]