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Re: Gurus? Care to re-explain the absense of gh_set_x() for me?
From: |
Neil Jerram |
Subject: |
Re: Gurus? Care to re-explain the absense of gh_set_x() for me? |
Date: |
16 Jul 2001 19:53:22 +0100 |
User-agent: |
Gnus/5.0808 (Gnus v5.8.8) Emacs/20.7 |
>>>>> "Miroslav" == Miroslav Silovic <address@hidden> writes:
Miroslav> Actually gh_set_x changes the _binding_ of a variable,
Miroslav> rather than modifying the value it's bound
Miroslav> to.
Hmm. That's not quite right, according to the usual terminology (at
least as I understand it).
In Scheme, a variable name is bound to a location (or `cell'), and a
value can be stored in that location. The binding between a name and
a location never changes (modulo effects of shadowing and going out of
scope). `(set! NAME VAL)' replaces the existing value in the location
bound to NAME by the new value VAL.
(And, of course, gh_set_x does nothing, because it doesn't exist :-).)
Miroslav> Basically, a variable in Scheme is simply a name for
Miroslav> a particular writable cell that contains one SCM, and
Miroslav> SCM itself is _not_ a cell (in particular, integers in
Miroslav> Guile are not represented by pointers to a box, they're
Miroslav> recognised by a particular bit-pattern of a SCM value).
Hang on, didn't I just say that! :-) (But the two halves of your post
rather contradicted each other IMO.)
Neil
- Re: Gurus? Care to re-explain the absense of gh_set_x() for me?, (continued)
- Re: Gurus? Care to re-explain the absense of gh_set_x() for me?, Alex Shinn, 2001/07/13
- Re: Gurus? Care to re-explain the absense of gh_set_x() for me?, Sam Tregar, 2001/07/13
- Re: Gurus? Care to re-explain the absense of gh_set_x() for me?, Alex Shinn, 2001/07/13
- Re: Gurus? Care to re-explain the absense of gh_set_x() for me?, Sam Tregar, 2001/07/13
- Re: Gurus? Care to re-explain the absense of gh_set_x() for me?, Eric E Moore, 2001/07/13
- Re: Gurus? Care to re-explain the absense of gh_set_x() for me?, Rob Browning, 2001/07/13
- Re: Gurus? Care to re-explain the absense of gh_set_x() for me?, Miroslav Silovic, 2001/07/15
- Re: Gurus? Care to re-explain the absense of gh_set_x() for me?, Rob Browning, 2001/07/16
- Re: Gurus? Care to re-explain the absense of gh_set_x() for me?, Neil Jerram, 2001/07/14
- Re: Gurus? Care to re-explain the absense of gh_set_x() for me?, Miroslav Silovic, 2001/07/15
- Re: Gurus? Care to re-explain the absense of gh_set_x() for me?,
Neil Jerram <=
- Re: Gurus? Care to re-explain the absense of gh_set_x() for me?, Miroslav Silovic, 2001/07/15
- Re: Gurus? Care to re-explain the absense of gh_set_x() for me?, Matthias Koeppe, 2001/07/13
- Re: Gurus? Care to re-explain the absense of gh_set_x() for me?, Sam Tregar, 2001/07/13
- Re: Gurus? Care to re-explain the absense of gh_set_x() for me?, Brett Viren, 2001/07/13
- Re: Gurus? Care to re-explain the absense of gh_set_x() for me?, Sam Tregar, 2001/07/13
- Re: Gurus? Care to re-explain the absense of gh_set_x() for me?, tom, 2001/07/13
- Re: Gurus? Care to re-explain the absense of gh_set_x() for me?, Matthias Koeppe, 2001/07/13
- Re: Gurus? Care to re-explain the absense of gh_set_x() for me?, Sam Tregar, 2001/07/13
- Re: Gurus? Care to re-explain the absense of gh_set_x() for me?, Matthias Koeppe, 2001/07/13
- Re: Gurus? Care to re-explain the absense of gh_set_x() for me?, Sam Tregar, 2001/07/13