[Emacs-diffs] master 2cc23f1: Finalizer documentation, minor improvements

[Daniel Colascione]

branch: master
commit 2cc23f170f920cbfc9df4c28bce6ca9d82c4e6cd
Author: Daniel Colascione <address@hidden>
Commit: Daniel Colascione <address@hidden>

    Finalizer documentation, minor improvements
    
    * doc/lispref/objects.texi (Finalizer Type): New section
    (Type Predicates): Mention finalizers in `type-of' documentation.
    * doc/lispref/elisp.texi (Top): Link to finalizer type.
    
    * src/data.c (Ftype_of): Make `type-of' work with finalizers.
    (syms_of_data): Register Qfinalizer.
    
    * src/print.c (print_object): Print whether a finalizer has
    been called.
    
    * test/automated/finalizer-tests.el (finalizer-object-type): Test that
    `type-of' works correctly for finalizers.
---
 doc/lispref/ChangeLog             |    6 ++++++
 doc/lispref/elisp.texi            |    1 +
 doc/lispref/objects.texi          |   37 ++++++++++++++++++++++++++++++++-----
 src/ChangeLog                     |    8 ++++++++
 src/data.c                        |    5 ++++-
 src/print.c                       |    5 ++++-
 test/ChangeLog                    |    5 +++++
 test/automated/finalizer-tests.el |    3 +++
 8 files changed, 63 insertions(+), 7 deletions(-)

diff --git a/doc/lispref/ChangeLog b/doc/lispref/ChangeLog
index e7d79d5..c27805b 100644
--- a/doc/lispref/ChangeLog
+++ b/doc/lispref/ChangeLog
@@ -1,3 +1,9 @@
+2015-03-03  Daniel Colascione  <address@hidden>
+
+       * objects.texi (Finalizer Type): New section for finalizer objects.
+       (Type Predicates): Mention finalizers in `type-of' documentation.
+       * elisp.texi (Top): Link to finalizer type.
+
 2015-03-02  Daniel Colascione  <address@hidden>
 
        * control.texi (Generators): New section
diff --git a/doc/lispref/elisp.texi b/doc/lispref/elisp.texi
index 3802e49..fc552be 100644
--- a/doc/lispref/elisp.texi
+++ b/doc/lispref/elisp.texi
@@ -316,6 +316,7 @@ Programming Types
 * Byte-Code Type::      A function written in Lisp, then compiled.
 * Autoload Type::       A type used for automatically loading seldom-used
                           functions.
+* Finalizer Type::      Runs code when no longer reachable.
 
 Character Type
 
diff --git a/doc/lispref/objects.texi b/doc/lispref/objects.texi
index ba28b63..b28b3b0 100644
--- a/doc/lispref/objects.texi
+++ b/doc/lispref/objects.texi
@@ -156,6 +156,8 @@ latter are unique to Emacs Lisp.
 * Byte-Code Type::      A function written in Lisp, then compiled.
 * Autoload Type::       A type used for automatically loading seldom-used
                         functions.
+* Finalizer Type::      Runs code when no longer reachable.
+
 @end menu
 
 @node Integer Type
@@ -1361,6 +1363,31 @@ in the loaded file.
 @code{autoload}, which stores the object in the function cell of a
 symbol.  @xref{Autoload}, for more details.
 
address@hidden Finalizer Type
address@hidden Finalizer Type
+
+  A @dfn{finalizer object} helps Lisp code clean up after objects that
+are no longer needed.  A finalizer holds a Lisp function object.
+When a finalizer object becomes unreachable after a garbage collection
+pass, Emacs calls the finalizer's associated function object.
+When deciding whether a finalizer is reachable, Emacs does not count
+references from finalizer objects themselves, allowing you to use
+finalizers without having to worry about accidentally capturing
+references to finalized objects themselves.
+
+Errors in finalizers are printed to @code{*Messages*}.  Emacs runs
+a given finalizer object's associated function exactly once, even
+if that function fails.
+
address@hidden make-finalizer function
+Make a finalizer that will run @var{function}.  @var{function} will be
+called after garbage collection when the returned finalizer object
+becomes unreachable.  If the finalizer object is reachable only
+through references from finalizer objects, it does not count as
+reachable for the purpose of deciding whether to run @var{function}.
address@hidden will be run once per finalizer object.
address@hidden defun
+
 @node Editing Types
 @section Editing Types
 @cindex editing types
@@ -1907,11 +1934,11 @@ types.  In most cases, it is more convenient to use 
type predicates than
 This function returns a symbol naming the primitive type of
 @var{object}.  The value is one of the symbols @code{bool-vector},
 @code{buffer}, @code{char-table}, @code{compiled-function},
address@hidden, @code{float}, @code{font-entity}, @code{font-object},
address@hidden, @code{frame}, @code{hash-table}, @code{integer},
address@hidden, @code{overlay}, @code{process}, @code{string},
address@hidden, @code{symbol}, @code{vector}, @code{window}, or
address@hidden
address@hidden, @code{finalizer}, @code{float}, @code{font-entity},
address@hidden, @code{font-spec}, @code{frame}, @code{hash-table},
address@hidden, @code{marker}, @code{overlay}, @code{process},
address@hidden, @code{subr}, @code{symbol}, @code{vector},
address@hidden, or @code{window-configuration}.
 
 @example
 (type-of 1)
diff --git a/src/ChangeLog b/src/ChangeLog
index 2f04d0b..930a33b 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,11 @@
+2015-03-03  Daniel Colascione  <address@hidden>
+
+       * print.c (print_object): Print whether a finalizer has
+       been called.
+
+       * data.c (Ftype_of): Make `type-of' work with finalizers.
+       (syms_of_data): Register Qfinalizer.
+
 2015-03-02  Daniel Colascione  <address@hidden>
 
        * print.c (print_object): Print finalizers.
diff --git a/src/data.c b/src/data.c
index 4770658..c96841a 100644
--- a/src/data.c
+++ b/src/data.c
@@ -223,7 +223,9 @@ for example, (type-of 1) returns `integer'.  */)
        case Lisp_Misc_Overlay:
          return Qoverlay;
        case Lisp_Misc_Float:
-         return Qfloat;
+          return Qfloat;
+        case Lisp_Misc_Finalizer:
+          return Qfinalizer;
        }
       emacs_abort ();
 
@@ -3547,6 +3549,7 @@ syms_of_data (void)
   DEFSYM (Qcons, "cons");
   DEFSYM (Qmarker, "marker");
   DEFSYM (Qoverlay, "overlay");
+  DEFSYM (Qfinalizer, "finalizer");
   DEFSYM (Qfloat, "float");
   DEFSYM (Qwindow_configuration, "window-configuration");
   DEFSYM (Qprocess, "process");
diff --git a/src/print.c b/src/print.c
index d391fd5..838d036 100644
--- a/src/print.c
+++ b/src/print.c
@@ -2046,7 +2046,10 @@ print_object (Lisp_Object obj, Lisp_Object printcharfun, 
bool escapeflag)
           break;
 
         case Lisp_Misc_Finalizer:
-          strout ("#<finalizer>", -1, -1, printcharfun);
+          strout ("#<finalizer", -1, -1, printcharfun);
+          if (NILP (XFINALIZER (obj)->function))
+            strout (" used", -1, -1, printcharfun);
+          strout (">", -1, -1, printcharfun);
           break;
 
          /* Remaining cases shouldn't happen in normal usage, but let's
diff --git a/test/ChangeLog b/test/ChangeLog
index 64ad851..3a311e9 100644
--- a/test/ChangeLog
+++ b/test/ChangeLog
@@ -1,3 +1,8 @@
+2015-03-03  Daniel Colascione  <address@hidden>
+
+       * automated/finalizer-tests.el (finalizer-object-type): Test that
+       `type-of' works correctly for finalizers.
+
 2015-03-02  Daniel Colascione  <address@hidden>
 
        * automated/generator-tests.el: New tests
diff --git a/test/automated/finalizer-tests.el 
b/test/automated/finalizer-tests.el
index 5308f01..4746dbe 100644
--- a/test/automated/finalizer-tests.el
+++ b/test/automated/finalizer-tests.el
@@ -76,3 +76,6 @@
       (should (equal
                (buffer-substring (point) (point-at-eol))
                "finalizer failed: (error \"ABCDEF\")")))))
+
+(ert-deftest finalizer-object-type ()
+  (should (equal (type-of (make-finalizer nil)) 'finalizer)))