Re: Defining functions on the fly

[Gene <gene.sullivan@gmail.com>]

On Monday, June 15, 2015 at 5:24:40 AM UTC-4, Andreas Röhler wrote:
> Hi,
> 
> have a bunch of subroutines which are useful in several modes - 
> beginning/end of expressions, string positions, comments etc.
> 
> Now every mode should get its own prefix.
> Can't write
> 
> (defun (concat "current-prefix-" foo) ())
> 
> as defun expects a symbol.
> 
> Exists "fset" - is there a recommended way to go?

I recommend using lambda to experimentally develop what you think of as a function of the sort defun is typically used typically used to define.

Once the function's actual definition is done via lambda it can be bound to a symbol via fset

(fset (function name-of-function)
 (lambda (arg)
  "docstring"
  ; Body goes here
 )
)

Of course the anonymous version of the function can be used via higher order functions such as `apply' and `mapcar' so function development and testing can be furthered before one gets around to deciding to keep it around and name it for convenient future use.

This strategy is pretty much applicable in Scheme as well

(define name-of-function
 (lambda (arg)
  ;body
 )
)

I hope this helps.

Gene