From: Mark Wooding <mdw@distorted.org.uk>
Date: Sat, 3 Aug 2019 14:20:46 +0000 (+0100)
Subject: src/class-make-{proto,impl}.lisp: Don't make duplicate initargs.
X-Git-Url: https://git.distorted.org.uk/~mdw/sod/commitdiff_plain/03570bbb9027efe5485d4776fc22d93ad410a892?hp=81054f0131824964d2cebfd7dec6f18be113020b

src/class-make-{proto,impl}.lisp: Don't make duplicate initargs.

If you set an initarg property on a slot definition which includes an
initializer then both the slot definition and the initializer act on the
initarg property and you end up with two initargs.  This isn't actually
a major problem, but it's ugly.

Add a new keyword argument to `make-sod-instance-initializer' to prevent
this from happening.
---

diff --git a/doc/meta.tex b/doc/meta.tex
index 2d1a577..4b42a86 100644
--- a/doc/meta.tex
+++ b/doc/meta.tex
@@ -166,7 +166,8 @@
 \begin{describe*}
     {\dhead{gf}
       {make-sod-instance-initializer
-          \=@<class> @<nick> @<name> @<value> @<pset> \&key :location
+          \=@<class> @<nick> @<name> @<value> @<pset> \\
+          \>\&key :inhibit-initargs :location
         \nlret @<init>}
      \dhead{gf}
       {make-sod-class-initializer
diff --git a/src/class-make-impl.lisp b/src/class-make-impl.lisp
index 5fe9de7..4785d9c 100644
--- a/src/class-make-impl.lisp
+++ b/src/class-make-impl.lisp
@@ -115,7 +115,7 @@
 ;;; Slot initializers.
 
 (defmethod make-sod-instance-initializer
-    ((class sod-class) nick name value pset &key location)
+    ((class sod-class) nick name value pset &key location inhibit-initargs)
   (with-default-error-location (location)
     (let* ((slot (find-instance-slot-by-name class nick name))
 	   (initarg-name (get-property pset :initarg :id))
@@ -126,7 +126,7 @@
       (with-slots (instance-initializers) class
 	(unless (or initarg-name initializer)
 	  (error "Slot initializer declaration with no effect"))
-	(when initarg-name
+	(when (and initarg-name (not inhibit-initargs))
 	  (make-sod-slot-initarg-using-slot class initarg-name slot pset
 					    :location location))
 	(when initializer
diff --git a/src/class-make-proto.lisp b/src/class-make-proto.lisp
index a2783ee..5622dc6 100644
--- a/src/class-make-proto.lisp
+++ b/src/class-make-proto.lisp
@@ -86,7 +86,7 @@
 
 (export 'make-sod-instance-initializer)
 (defgeneric make-sod-instance-initializer
-    (class nick name value pset &key location)
+    (class nick name value pset &key location inhibit-initargs)
   (:documentation
    "Construct and attach an instance slot initializer, to CLASS.
 
@@ -95,7 +95,13 @@
    construction process.  The default method looks up the slot using
    `find-instance-slot-by-name', calls `make-sod-initializer-using-slot' to
    actually make the initializer object, and adds it to the appropriate list
-   in CLASS."))
+   in CLASS.
+
+   Usually, if an `initarg' property is set on PSET, then a slot initarg is
+   created and attached to the slot; this can be prevented by setting
+   INHIBIT-INITARGS non-nil.  This is needed when creating a slot and
+   initializer from the same property set, in order to prevent creation of a
+   duplicate initarg."))
 
 (export 'make-sod-class-initializer)
 (defgeneric make-sod-class-initializer