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Diffstat (limited to 'compat.texi')
| -rw-r--r-- | compat.texi | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/compat.texi b/compat.texi index 6b2862a..a56d511 100644 --- a/compat.texi +++ b/compat.texi @@ -3459,6 +3459,27 @@ older than 31.1. Note that due to upstream changes, it might happen that there will be the need for changes, so use these functions with care. +@c copied from lispref/lists.texi +@defun ensure-proper-list object +This function returns @var{object} as a proper list (@pxref{(elisp) Cons +Cells}). If @var{object} is already a proper list, the function returns +it; otherwise, the function returns a one-element list containing +@var{object}. + +If @var{object} might be a long list, prefer @code{ensure-list}, because +the latter function runs in constant time, whereas +@code{ensure-proper-list} runs in linear time. For short lists this +function is a convenient way to treat cons-cells as non-lists: + +@lisp +(ensure-list '(1 . 2)) + @result{}(1 . 2) + +(ensure-proper-list '(1 . 2)) + @result{}((1 . 2)) +@end lisp +@end defun + @c based on lisp/subr.el @defun set-local variable value Make @var{variable} buffer local and set it to @var{value}. |