Re: [Gimp-user] Help! Problem with gimp-curves-spline procedure

[Kevin Cozens <kevin ve3syb ca>]

On 12-05-09 06:44 AM, Adir Kol wrote:
> *(define spoint 15)*
> *(gimp-curves-spline drawable 0 6 #(0 0 0  spoint  255 255))*
>
> I get an error: *Error: Item 4 in vector is not a number (argument 4 for
> function gimp-curves-spline) #( 0 0 0  spoint  255 255 )*

Putting a variable name in a list (or vector in this case) and expecting the 
value held by the variable to become part of the list (or vector) is an 
often made error when writing Scheme scripts. The syntax #( objects ) is a 
vector containing the listed objects. It is *not* an expression that 
evaluates to a list. To put it another way, it will not use the value or 
contents of "spoint" in the vector. The "spoint" reference was treated as a 
symbol.

It is easy to solve the problem by using the "list" procedure, but in your 
case you want a vector so you need one additional procedure call.

Use the following:
    (list->vector (list 0 0 0 spoint 255 255))

--
Cheers!

Kevin.

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