Returns a quoted expression, where parts of the expression
wrapped in ".()" are evaluated in the environment
specified by the
where argument.
USAGE:
bquote(expr, where=parent.frame())
REQUIRED ARGUMENTS:
expr
a S-PLUS expression that can include terms wrapped in ".()" which says
to evaluate the enclosed term.
OPTIONAL ARGUMENTS:
where
either an integer specifying a frame or a list of named elements defining the
names occurring in the expression.
This argument is similar to
the
local argument in the function
eval and
the
frame argument in the function
substitute.
VALUE:
an expression similar to the input expression but with all terms
wrapped in ".()" replaced by their values.
SIDE EFFECTS:
Expressions that are wrapped in ".()" will be evaluated and can have side
effects.
DETAILS:
This function emulates R's
bquote function,
but is implemented using the S-PLUS function
rapply.
bquote
is similar in function to the LISP
backquote
macro.