R package: lobstr

lobstr provides a set of tools for inspecting and undersanding R data structures.

ast() - Abstract Syntax Tree

ast(…) prints the abstract syntax tree of the given code passed to the function:

library(lobstr)

ast( if (x > y) yes() else no() );
#
#  o-`if` 
#  +-o-`>` 
#  | +-x 
#  | \-y 
#  +-o-yes 
#  \-o-no