nondestructive push

[Dmi]

How can I construct a function, that nondestructive appends an element to a list and return modified list?

I wrote so:

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(define (print-ln) (print (join (append (args) (list "n")))))
But the idea is so usual, that I suspect, there is more fine way, without using

(append lst (list one-element))



... I use 'print-ln' insead of println under windows to handle unix-generated text files.

[pjot]

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(define (mypush) (flat (append (args))))

> (set 'lst (mypush 1 2 3))
(1 2 3)
> (mypush lst 4)
(1 2 3 4)


...or is this not what you want?



Peter

[newdep]

Thats destructive, DMI ment non-destrutive ;-)

[pjot]

It's non destructive:

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> (set 'lst (mypush 1 2 3))
(1 2 3)
> (mypush lst 4)
(1 2 3 4)
> (println lst)
(1 2 3)


[newdep]

Its surly is ...:)