(Sets And Lists): Add memql.

1 files changed, 21 insertions, 0 deletions

diff --git a/lispref/lists.texi b/lispref/lists.texi
index 1c6247d818..17ed62a6d6 100644
--- a/lispref/lists.texi
+++ b/lispref/lists.texi
@@ -1395,6 +1395,27 @@ The function @code{delq} offers a way to perform this operation
 destructively.  See @ref{Sets And Lists}.
 @end defun
 
+@defun memql object list
+The function @code{member} tests to see whether @var{object} is a member
+of @var{list}, comparing members with @var{object} using @code{eql},
+so floating point elements are compared by value.
+If @var{object} is a member, @code{memql} returns a list starting with
+its first occurrence in @var{list}.  Otherwise, it returns @code{nil}.
+
+Compare this with @code{memq}:
+
+@example
+@group
+(memql 1.2 '(1.1 1.2 1.3)  ; @r{@code{1.2} and @code{1.2} are @code{eql}.}
+     @result{} (1.2 1.3)
+@end group
+@group
+(memq 1.2 '(1.1 1.2 1.3)  ; @r{@code{1.2} and @code{1.2} are not @code{eq}.}
+     @result{} nil
+@end group
+@end example
+@end defun
+
 The following three functions are like @code{memq}, @code{delq} and
 @code{remq}, but use @code{equal} rather than @code{eq} to compare
 elements.  @xref{Equality Predicates}.