A variable number of Variables

[Anonymous]

I am looking for some help to create some code to create and assign values to a number of variables - such as A1, A2, A3  ....An,  where n is a variable number depending on the circumstances of external data.   

I have done this in the very long distant past, but I have forgotten and/or lost the knack or coding technique, although I think that it used the (read) or (set) functions. 

I have to extract strings from a command and quote delimited file from Excel on a per line basis (e.g. "text1", "text2", "text3") and subsequently assign A1 to "text1", A2 to "text2" etc but the number of strings is variable  - depending on the project.

Can someone please help me get started.

Thanks

George in New Zealand

[Shneuph · Accepted solution]

[Ranjit_Singh]

Let's assume you read the excel file and got all the data in a list like

(setq lst ("text1" "text2" "text3".....))

you can do this to assign each to a variable

(setq lst '("text1" "text2" "text3")
      ctr 0)
(mapcar '(lambda (x) (setq ctr (1+ ctr)) (set (read (strcat "A" (itoa ctr))) x)) lst)

[scot-65]

In my opinion Ranjit's first code quote is all that is needed.

He is showing a variable that contains a undetermined number
of items that can be directly accessed using NTH.

(nth 1 lst) = "text1"
(nth 3 lst) = "text3"
...

Use LENGTH to determine how many members are in the list.
CONS is your friend to build the initial list (then reverse the list
when the last one is fetched).

???

[dgorsman]

Lists (it is the "L" in LISP, after all)!  If sequential indexing is impractical, then use dotted pairs.  Note that "dotted pairs" aren't restricted to a single value as (index . value), the "value" can be a list itself, which may be a list of dotted pairs, which could be a list, and so on.

[Anonymous]

Many thanks for wonderful solution 🙂