Re: scheme/dsssl question

[Chris Maden <crism@xxxxxxx>]

[Henry Thompson]
> The normal strategy to get around this feature is to use thunks,
> i.e. procedural closures of no arguments:
> 
> (define (dblappl fn thunk) (fn (thunk) (thunk)))
> 
> (let ((foo 3)) (dblappl + (lambda () foo)))
> 
> The thunk of necessity carries its lexical environment with it,
> achieving the encapsulation you need.
> 
> Hope this helps

I don't think this helps with Norm's question, where a string or
symbol is passed as an argument to a function which then finds the
value of the object defined with that name.

(define foo
  3)

(define bar
  ... )

such that (bar 'foo) will return 3 or some function thereof.  Would
thunks work here?

(define (bar thunk)
  (thunk))

or better yet,

(define (bar thunk)
  (if (string? thunk)
    ((string->symbol thunk))
    (thunk)))

-Chris
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