Re: Colors in alists

[Thomas Morley]

2014-11-04 19:05 GMT+01:00 Urs Liska <address@hidden>:
>
> Am 04.11.2014 15:47, schrieb Jay Anderson:
>>
>> On Tue, Nov 4, 2014 at 3:48 AM, Urs Liska <address@hidden> wrote:
>>>
>>> I want to store colors in an alist like
>>>
>>> #(define types
>>> '(("one" . "red")
>>> ("two" . "blue")))
>>>
>>> I can retrieve and display the values with assoc-ref but I don't know how
>>> to
>>> turn the returned string into a color to be used in an override.
>>
>> Try quasiquote + unquote:
>>
>> #(define types
>>    `(("one" . ,red)
>>      ("two" . ,blue)))
>>
>> #(display types) => ((one 1.0 0.0 0.0) (two 0.0 0.0 1.0))
>>
>> -----Jay
>
>
> Hi Jay,
>
> thanks, that was it. Still a mystery, this all ...
>
> I would be extremely happy if someone could take the time and write a
> slow-paced tutorial about this on Scores of Beauty!
>
> Best
> Urs
>
>
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As others pointed out it's a matter of quote/unquote/quasiquote,
though for completeness, there is some lilypond function which can
make your initial approach work:


#(define clrs
'(("one" . "red")
  ("two" . "blue")))

#(display (color? (x11-color (assoc-get "one" clrs))))
#(display (x11-color (assoc-get "one" clrs)))


Cheers,
  Harm