Man pages for hadley/lazyeval
Lazy (Non-Standard) Evaluation

all_dots	Combine explicit and implicit dots.
as.lazy	Convert an object to a lazy expression or lazy dots.
as_name	Coerce an object to a name or call.
ast_	Display a call (or expression) as a tree.
auto_name	Automatically name all components of a lazy dots.
call_modify	Modify the arguments of a call.
call_new	Create a call by "hand"
common_env	Find common environment in list of lazy objects.
expr_label	Find the expression associated with an argument
f_capture	Make a promise explicit by converting into a formula.
f_eval	Evaluate a formula
f_interp	Interpolate a formula
f_list	Build a named list from the LHS of formulas
f_new	Create a formula object by "hand".
f_rhs	Get/set formula components.
f_text	Turn RHS of formula into a string/label.
function_new	Create a function by "hand"
f_unwrap	Unwrap a formula
interp	Interpolate values into an expression.
is_formula	Is object a formula?
is_lang	Is an object a language object?
lazy_	Capture expression for later lazy evaluation.
lazy_dots	Capture ... (dots) for later lazy evaluation.
lazy_eval	Evaluate a lazy expression.
make_call	Make a call with 'lazy_dots' as arguments.
missing_arg	Generate a missing argument.