[racket] struct constructors

It is not what you need.

When you create a new structure, the constructor is the thing that
makes it... in your example that's "blah". The keyword you mentioned
lets you change that name to something like "mother-in-law", so

(struct blah (a b c v) #:constructor-name mother-in-law)

(mother-in-law 1 2 3 4)

is a valid program.

You may find this useful if you want to write your style struct
constructor but name it "blah".

Jay


On Tue, May 27, 2014 at 1:25 AM, Aidan Gauland <aidalgol at amuri.net> wrote:
> Hello fellow racketeers,
>
> What's the nearest equivalent for a struct to constructors for class
> instances?  Say I have a struct with a field that should be initialised
> to a three-element vector.  Right now, I'm just defining a wrapper
> make-blah.
>
> (struct blah (a b c v))
>
> (define (make-blah)
>   (blah 0 0 0 #(0 0 0))
>
> This seems fine, but I see that there's a keyword argument to the
> `struct' procedure #:constructor-name and I can't quite make sense of
> what that does.  Is it a low-level thing, or is it exactly what I want?
>
> Thanks,
> Aidan Gauland
>
>
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-- 
Jay McCarthy <jay at cs.byu.edu>
Assistant Professor / Brigham Young University
http://faculty.cs.byu.edu/~jay

"The glory of God is Intelligence" - D&C 93