In article
<a31162a4-bde0-4a97-8193-39c81857b07f@[EMAIL PROTECTED]
> nour
<nour.laouini@[EMAIL PROTECTED]
> writes:
>hello,
>
>I have a problem:
>
>I want to update the last element in a skill list by incrementing it ,
>for example I have the following list: list='(4 6) and I want to
>transform it to this one list='(4 7).
>
>There is a skill fonction which can do it: rplacd(name_liste
>new_value) but it works only when I give the exact new_value, for
>example i must tape
> rplacd( list '(7))
>
>Please help me because i must use it in a "for" fonction so the
>incrementation must happen automatically ....
>
>I've tried this but it didn't work:
>
>y=nth( 1 list)+1
>rplacd( list '(y))
>
>it generate the following list: (4 y)
>
>thanks a lot for the one who will help me
It's replacing the last element with the symbol y because that's what you
are telling it to do. The single quote in front of the open paren says
"don't evaluate symbols, pass them as is".
if you do:
y = nth( 1 list )+1
rplacd( list list(y) )
it will do what you are asking for, since the list function evaluates its
arguments.
The following will also work:
y = list( nth( 1 list )+1 )
rplacd( list y )
Your statement:
rplacd( list '(y) )
is equivalent to:
rplacd( list list( 'y ) )
-Pete Zakel
(phz@[EMAIL PROTECTED]
)
Felson's Law:
To steal ideas from one person is plagiarism; to steal from
many is research.
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