memory costs of storing lambdas?

[Han-Wen Nienhuys]

(please CC replies, I'm not subscribed to guile-user)

Hi there,

I have a small question: I was wondering how much memory it costs to
store an anonymous function.  I have to make choices between storing
various entities in lilypond either as a function, or as an
expression.

The following fictional example illustrates the distinction (#
introduces in-line Scheme in Lilypond syntax):


1. using anon functions:

  (define (style-setter style)
    (lambda (head) (set-note-head-style head style)))
  ...

  \property Voice.NoteHead \set #'style-procedure
    = #(style-setter "cross")

During the lilypond run, the anonymous function is called. Storage
cost: one anonymous function

2. using expressions

  \property Voice.NoteHead \set #'style-expression
    = #(list set-note-head-style "cross")

During the lilypond-run, a note-head pointer is prepended to the
argument list, and the list (set-note-head-style head style) is
evaluated.

Storage cost: a list of length 2.


I have the feeling that solution 1. is more expensive in terms of
memory than solution 2. My question: is this true, and how could I
have found out this answer myself? (i.e. where is the related
interpreter code?)

Thanks,

Han-Wen

-- 

Han-Wen Nienhuys   |   address@hidden   |   http://www.cs.uu.nl/~hanwen