Hi Neil,
Neil Jerram <[EMAIL PROTECTED]> writes:
> [EMAIL PROTECTED] (Ludovic Courtès) writes:
>
>> I'm not sure whether Mikael Djurfeldt is actually following this list so
>> perhaps somebody else would like to give their opinion about these
>> documentation bits?
>>
>> Thanks,
>> Ludovic.
>>
>> [0] http://lists.gnu.org/archive/html/guile-devel/2006-03/msg00005.html
>
> I'm trying to clear out old email... Would you mind reposting the
> remaining patch if you still have it; unfortunately the texinfo is
> mangled in the HTML copy.
In the meantime, Marius (IIRC) applied a more concise version of this
patch, without the example (sorry, I couldn't find the post in question,
but see changelog entry dated 2006-03-08).
Anyway, I re-issued a patch that should apply to the current CVS HEAD.
Thanks,
Ludovic.
--- orig/doc/goops/goops.texi
+++ mod/doc/goops/goops.texi
@@ -26,7 +26,7 @@
@ifinfo
This file documents GOOPS, an object oriented extension for Guile.
-Copyright (C) 1999, 2000, 2001, 2003, 2006 Free Software Foundation
+Copyright (C) 1999, 2000, 2001, 2003 Free Software Foundation
Permission is granted to make and distribute verbatim copies of
this manual provided the copyright notice and this permission notice
@@ -61,7 +61,7 @@
@c start the copyright page.
@page
@vskip 0pt plus 1filll
-Copyright @copyright{} 1999, 2006 Free Software Foundation
+Copyright @copyright{} 1999 Free Software Foundation
Permission is granted to make and distribute verbatim copies of
this manual provided the copyright notice and this permission notice
@@ -833,13 +833,40 @@
@deffnx {slot option} #:init-keyword init-keyword
These options provide various ways to specify how to initialize the
slot's value at instance creation time. @var{init-value} is a fixed
-value (shared across all new instances of the class).
[EMAIL PROTECTED] is a procedure of no arguments that is called
-when a new instance is created and should return the desired initial
-slot value. @var{init-form} is an unevaluated expression that gets
+value, @emph{shared across all new instances of the class}.
[EMAIL PROTECTED] is a procedure of no arguments that is called when a
+new instance is created and should return the desired initial slot
+value. @var{init-form} is an unevaluated expression that gets
evaluated when a new instance is created and should return the desired
-initial slot value. @var{init-keyword} is a keyword that can be used to
-pass an initial slot value to @code{make} when creating a new instance.
+initial slot value. @var{init-keyword} is a keyword that can be used
+to pass an initial slot value to @code{make} when creating a new
+instance.
+
+Note that since the @code{init-value} is shared across new instances
+of a class, you may only use it when the initial value is an immutable
+value, like a constant. If you want to initialize a slot with a
+fresh, mutable value, you should use @code{init-thunk} instead to make
+sure that each new instance's slot is initialized with a new object.
+Consider the following example:
+
[EMAIL PROTECTED]
+(define-class <chbouib> ()
+ (hashtab #:init-value (make-hash-table)))
[EMAIL PROTECTED] example
+
+Here, only one hash table is created, and all instances of
[EMAIL PROTECTED]<chbouib>} have their @code{hashtab} slot refer to it. In order
+to have each instance of @code{<chbouib>} initialized with a new hash
+table, you have to proceed as follow:
+
[EMAIL PROTECTED]
+(define-class <chbouib> ()
+ (hashtab #:init-thunk make-hash-table))
[EMAIL PROTECTED] example
+
+Here, @code{make-hash-table} will be called each time a new instance
+of @code{<chbouib>} is created, thus initializing each @code{hashtab}
+slot with a new hash table.
If more than one of these options is specified for the same slot, the
order of precedence, highest first is
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