* calc/calc.el (calc-context-sensitive-enter): New variable.

  (calc-enter): Use `calc-context-sensitive-enter'.

* doc/misc/calc.texi (Customizing Calc): Mention the new variable
  `calc-context-sensitive-enter'.

4 files changed, 30 insertions, 2 deletions

diff --git a/doc/misc/ChangeLog b/doc/misc/ChangeLog
index 976922a3978..ca4169316c5 100644
--- a/doc/misc/ChangeLog
+++ b/doc/misc/ChangeLog
@@ -1,3 +1,8 @@
+2013-11-17  Jay Belanger  <jay.p.belanger@gmail.com>
+
+        * calc.texi (Customizing Calc): Mention new variable
+        `calc-context-sensitive-enter'.
+
 2013-11-12  Aaron Ecay  <aaronecay@gmail.com>
 
         * org.texi (Exporting code blocks): Document the 'inline-only
diff --git a/doc/misc/calc.texi b/doc/misc/calc.texi
index 04160eafad0..0154c82750a 100644
--- a/doc/misc/calc.texi
+++ b/doc/misc/calc.texi
@@ -35696,6 +35696,14 @@ have different dimensions. The default value of @code{calc-ensure-consistent-uni
 is @code{nil}.
 @end defvar
 
+@defvar calc-context-sensitive-enter
+The command @code{calc-enter} will typically duplicate the top of the
+stack.  If @code{calc-context-sensitive-enter} is non-@code{nil},
+then the @code{calc-enter} will copy the element at the cursor to the
+top of the stack.  The default value of
+@code{calc-context-sensitive-enter} is @code{nil}.
+@end defvar
+
 @defvar calc-undo-length
 The variable @code{calc-undo-length} determines the number of undo
 steps that Calc will keep track of when @code{calc-quit} is called.
diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 2b4f941048c..faa2243ca3b 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,8 @@
+2013-11-17  Jay Belanger  <jay.p.belanger@gmail.com>
+
+        * calc/calc.el (calc-context-sensitive-enter): New variable.
+        (calc-enter): Use `calc-context-sensitive-enter'.
+
 2013-11-16  Teodor Zlatanov  <tzz@lifelogs.com>
 
         * progmodes/cfengine.el: Version bump.
diff --git a/lisp/calc/calc.el b/lisp/calc/calc.el
index 2795a177a41..72d456957c7 100644
--- a/lisp/calc/calc.el
+++ b/lisp/calc/calc.el
@@ -146,6 +146,7 @@
 (declare-function calc-set-language "calc-lang" (lang &optional option no-refresh))
 (declare-function calc-edit-finish "calc-yank" (&optional keep))
 (declare-function calc-edit-cancel "calc-yank" ())
+(declare-function calc-locate-cursor-element "calc-yank" (pt))
 (declare-function calc-do-quick-calc "calc-aent" ())
 (declare-function calc-do-calc-eval "calc-aent" (str separator args))
 (declare-function calc-do-keypad "calc-keypd" (&optional full-display interactive))
@@ -426,6 +427,13 @@ when converting units."
   :version "24.3"
   :type 'boolean)
 
+(defcustom calc-context-sensitive-enter
+  nil
+  "If non-nil, the stack element under the cursor will be copied by `calc-enter'."
+  :group 'calc
+  :version "24.4"
+  :type 'boolean)
+
 (defcustom calc-undo-length
   100
   "The number of undo steps that will be preserved when Calc is quit."
@@ -2257,8 +2265,10 @@ the United States."
          ((= n 0)
           (calc-push-list (calc-top-list (calc-stack-size))))
          (t
-          (calc-push-list (calc-top-list n))))))
-
+          (if (not calc-context-sensitive-enter)
+              (calc-push-list (calc-top-list n))
+            (let ((num (max 1 (calc-locate-cursor-element (point)))))
+              (calc-push-list (calc-top-list n num))))))))
 
 (defun calc-pop (n)
   (interactive "P")