-The placement of automatic beams is determined by the time signature.
-Three types of rules are used for determining the end of automatic
-beams: @emph{default} rules
-for the time signature, @emph{explicit} rules for the beam in the time
-signature, and the @emph{beatLength} for the time signature.
-
-The following rules, in order of priority, apply when determining
-the appearance of beams:
-
-@itemize
-
-@item If a manual beam is specified with @code{[..]} set the beam
-as specified, otherwise
-
-@item if @code{\autoBeamOff} is in force do not beam, otherwise
-
-@item if an explicit beam-ending rule is defined for the beam type
-in the time signature, use it to determine the valid
-places where beams may end, otherwise
-
-@item if a default beam-ending rule is defined in the time signature,
-use it to group notes with beams, otherwise
-
-@item use the value of @code{beatLength} to group notes with beams
-
-@end itemize
-
-@i{@strong{Modifying the grouping of beats}}
-
-By default @code{beatLength} is
-derived from the time signature set by the @code{\time} command.
-The @code{beatLength} is set to be one over the denominator
-of the time signature.
-
-@code{beatLength} is a @i{moment},
-a unit of musical duration. A quantity of type @i{moment} is
-created by the scheme function @code{ly:make-moment}. For more
-information about this function, see @ref{Time administration}.
-
-Autobeam and beam subdivide settings are stored in the
-@code{beamSettings} property. Default values of @code{beamSettings}
-are determined in @file{scm/@/beam@/-settings@/.scm}. Entries in
-@code{beamSettings} are indexed by time signature and
-rule type.
-
-Time signature should be a scheme pair , e.g. @code{#'(4 . 4)}.
-
-Rule type should be @code{#'end} for beam ending and @code{#'subdivide} for
-beam subdivision.
-
-The ending and subdivision rules consist of a scheme alist
-(or list of pairs) that
-indicates the beam type and the grouping to be applied to that
-beam type.
-
-@example
-#'((beam-type1 . grouping-1)
- (beam-type2 . grouping-2)
- (beam-type3 . grouping-3))
-@end example
-
-Beam type is either a scheme pair indicating the duration
-of the beam, e.g. @code{(1 . 16)}, or @code{*} to indicate a
-default rule, which applies to all beams if no explicit rule is
-defined.
-
-Grouping is a scheme list indicating the grouping to be applied to
-the beam. For default rules (where beam type is
-@code{*}, the grouping is in units of @code{beatLength}.
-For explicit rules, the grouping is in units of the beam type.
-
-Beam settings are changed with
-@code{\overrideBeamSettings} and @code{\revertBeamSettings}.
+In most instances, automatic beams will end at the end of a beat.
+The ending points for beats are determined by the context properties
+@code{baseMoment} and @code{beatStructure}. @code{beatStructure}
+is a scheme list that defines the length of each beat in the measure
+in units of @code{baseMoment}. By default, @code{baseMoment} is
+the one over numerator of the time signature. By default,
+each unit of length @code{baseMoment} is a single beat.