Commit 1334cc0c authored by Kim F. Storm's avatar Kim F. Storm
Browse files

(Sets And Lists): Add memql.

parent 3075e881
......@@ -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}.
......
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