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From: ludo@gnu.org (Ludovic Courtès)
To: guile-devel@gnu.org
Subject: FFI and disjoint types
Date: Mon, 01 Mar 2010 15:18:59 +0100	[thread overview]
Message-ID: <87sk8kgm5o.fsf@gnu.org> (raw)

Hello,

The nice thing about SMOBs is that they allow disjoint C types to be
mapped to disjoint Scheme types.

With ‘(system foreign)’, C pointers are mapped to Scheme foreign
objects, regardless of the type of object pointed to.  Thus, to get
disjoint types in Scheme, foreign objects would need to be boxed in
structs (since structs are the only way to create disjoint types from
Scheme).

If this analysis is correct, the resulting code may be somewhat
inefficient since we end up boxing C pointers twice.

Is this correct?  Thoughts?

Thanks,
Ludo’.





             reply	other threads:[~2010-03-01 14:18 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-03-01 14:18 Ludovic Courtès [this message]
2010-03-01 20:49 ` FFI and disjoint types Neil Jerram
2010-03-03 12:24 ` Andy Wingo

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