why don't this work?

[ericsm]

why doesn't the following work?



(define (addcustomer )

  (set 'namee (read-line))

  (set 'street (read-line))

  (push '((namee) (street)))customer)



The part that isn't working is: (push '((namee) (street)))customer)

[Lutz]

Try this program:

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; test
(define (addcustomer)
        (set 'namee (read-line))
        (set 'street (read-line))
        (push (list namee street)  customer))


now execute it:

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~> newlisp test
newLISP v.8.8.0 on OSX UTF-8, execute 'newlisp -h' for more info.

> (addcustomer)
John Doe
123 Main Street, Anytown    
("John Doe" "123 Main Street, Anytown")
>


Lutz

[cormullion]

As for why. First:

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(namee)

is trying unsuccessfully to evaluate the first item in this list as the function namee.



But:

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'(namee street)

will produce (namee street), because the quote prevents these symbols from being evaluated.



So your original code:

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'((namee) (street)))

is doing two things that you don't want: preventing evaluation of a list of lists, and trying to evaluate those lists and failing to find useful functions.



WIthout the doubled parentheses:

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(push '(namee street) customer)

you would have a nice unevaluated list of symbols:

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> (push '(namee street) customer)
(namee street)


Since namee contains information you want, evaluate it.