Re: if procedure

[Freeman Gilmore]

On Wed, Nov 27, 2019 at 10:32 AM Anders Eriksson <address@hidden> wrote:
>
>
> On 2019-11-27 14:20, Freeman Gilmore wrote:
>
> From Extending Lilypond:
>
> guile> (define a 3)
> guile> (define b 5)
> guile> (if (> a b) "a is greater than b" "a is not greater than b")
> "a is not greater than b"
>
> Note missing ")".
>
> No, it's not missing any ")"
>
> In Frescobaldi i tried:
>
> \version "2.19.83"
> #(define a 3)
> #(define b 5)
> #(display (if (> a b) "a is greater than b" "a is not greater than b")
> "a is not greater than b"))
>
>
> What is the code suppose to do?
> You define two variables, a and b, and give them a value.
> You then compare a and b and if a is greater than b then you write out a text 
> "a is greater than b" if not then you write out a different text "a is not 
> greater than b".
>
> Scheme is a Lisp based language and uses parentheses to group statements.
> The number of left parentheses should be the same as the number of right 
> parentheses!!!
>
> Your problem is the line
>
> #(display (if (> a b) "a is greater than b" "a is not greater than b")
>
> It has 3 left parentheses and 2 right parentheses.
> Frescobaldi is helpful and shows the matched parentheses when you put the 
> cursor on a a parentheses.
> Using this help you soon will find the the first left parentheses has no 
> right parentheses.
>
> The error will disappear if you add a right parentheses last on the line
> #(display (if (> a b) "a is greater than b" "a is not greater than b"))
>
> // Anders
That got it, i was reading the book wrong; i  was trying to include
the results as one of the choices.   I do not see the ")" in the book
but it does copy and past it ok.   Probably have the print to large.
Al is well.

Thank you,
fg