omitted in a call only when it can't get confused with a following
parameter of different type.
-Predicates with syntactical significance are @code{ly:pitch?},
-@code{ly:duration?}, @code{ly:music?}, @code{markup?}. Other
-predicates require the parameter to be entered as Scheme expression.
-
@code{result-type?} can specify a default in the same manner as
predicates, to be used in case of a type error in arguments or
result."
omitted in a call only when it can't get confused with a following
parameter of different type.
-Predicates with syntactical significance are @code{ly:pitch?},
-@code{ly:duration?}, @code{ly:music?}, @code{markup?}. Other
-predicates require the parameter to be entered as Scheme expression.
-
Must return a music expression. The @code{origin} is automatically
set to the @code{location} parameter."
omitted in a call only when it can't get confused with a following
parameter of different type.
-Predicates with syntactical significance are @code{ly:pitch?},
-@code{ly:duration?}, @code{ly:music?}, @code{markup?}. Other
-predicates require the parameter to be entered as Scheme expression.
-
Can return arbitrary expressions. If a music expression is returned,
its @code{origin} is automatically set to the @code{location}
parameter."
omitted in a call only when it can't get confused with a following
parameter of different type.
-Predicates with syntactical significance are @code{ly:pitch?},
-@code{ly:duration?}, @code{ly:music?}, @code{markup?}. Other
-predicates require the parameter to be entered as Scheme expression.
-
Must return an event expression. The @code{origin} is automatically
set to the @code{location} parameter."