Thanks for the quick reply, and the great info I get on this list. Maybe more to the point would be a function like so:
(de foo (Lst) # some kind of escape condition usually here (foo (modified-copy Lst)) ) Where modified-copy is a function that returns a *new* list. After, say, the tenth time foo is called, are there now ten lists in memory? Rationale: In some cases it feels safer and more natural to implement the algorithm as a recursive algorithm where you are always passing around modified copies of the data. Or do we have to use loops and set a variable each iteration? On 02/25/2017 11:06 PM, Alexander Burger wrote: > On Sun, Feb 26, 2017 at 08:31:37AM +0100, Alexander Burger wrote: >> (let A (bar (copy Lst)) >> (off Lst) >> (doSomethingWithTheCopy) >> ... >> >> With (off Lst) *one* refernce to the list is cleared, but the list will be >> garbage collected only when the *last* reference is gone, which is not under >> control of 'foo'. > > Of course, if you *know* that 'Lst' is not owned by anybody else, i.e. it was > freshly created by reading or list manipulations etc., you don't need to copy > it > at all in the first place. 'copy' is used rather seldom, in cases where you > want > to do destructive operations on list that might be owned by someone else. > > ♪♫ Alex > -- https://qlfiles.net -- UNSUBSCRIBE: mailto:picolisp@software-lab.de?subject=Unsubscribe
