Re: [racket-users] How to check if a symbol is defined before calling it?

Glad you found something that works! For the record, being in a pkg and being an app are not mutually exclusive. DrRacket, for example, enjoys both statuses. Robby On Sun, Feb 18, 2018 at 5:41 PM Alex Harsanyi wrote: > > Hi Robby, > > On Sunday, February 18, 2018 at

Re: [racket-users] How to check if a symbol is defined before calling it?

Hi Robby, On Sunday, February 18, 2018 at 10:33:09 AM UTC+8, Robby Findler wrote: > > FWIW, the approach that is less friendly to your clients but perhaps > easier for you (and maybe good enough for them) is to declare a > dependency on a specific version in the info.rkt file of your pkg. The

Re: [racket-users] How to check if a symbol is defined before calling it?

FWIW, the approach that is less friendly to your clients but perhaps easier for you (and maybe good enough for them) is to declare a dependency on a specific version in the info.rkt file of your pkg. The pkg system will ensure that the latest version is used. Robby On Sat, Feb 17, 2018 at 8:31

Re: [racket-users] How to check if a symbol is defined before calling it?

Hi Philip, Thanks for the quick reply, yes this strategy seemed to solve the problem. Best Regards, Alex. On Sunday, February 18, 2018 at 10:03:07 AM UTC+8, Philip McGrath wrote: > > You could do it with dynamic-require: > > (let ([point-pict (dynamic-require 'plot 'point-pict (λ () #f))]) >

Re: [racket-users] How to check if a symbol is defined before calling it?

You could do it with dynamic-require: (let ([point-pict (dynamic-require 'plot 'point-pict (λ () #f))]) (when point-pict (point-pict ...))) -Philip On Sat, Feb 17, 2018 at 7:57 PM, Alex Harsanyi wrote: > > The recent plot library introduces a new function,

[racket-users] How to check if a symbol is defined before calling it?

The recent plot library introduces a new function, `point-pict` which is not yet available as part of a Racket distribution, and the plot package has to be installed separately from GitHub for this function. In my code I would like to be able to check if this function is available before