lex_xl takes an Excel formula and separates it into tokens. It returns a
dataframe, one row per token, giving the token itself, its type (e.g.
number, or error), and its level.
The parse tree is designed for analysis rather than computation, and may not support computation.
A simple plot() function is provided that depends on the suggested
package ggraph (which pulls in many other dependencies that can be tricky
to install).
lexl::lex_xl() Tokenise (lex) an Excel formula.
lexl::is_range() Test whether an Excel formula refers to a range of cells
plot.lexl(), lexl::lexl_igraph() Draw a simple tree plot of a parse
tree from lexl::lex_xl()
lexl::lexl_edges() Utility function used by plot.lexl() and
lexl::lexl_igraph()
lexl::lexl_vertices() Utility function used by plot.lexl() and
lexl::lexl_igraph()
lexl::lexl_igraph() Utility function used by plot.lexl() and
lexl::lexl_igraph()
lexl::demo_lexl() Shiny app to tokenise formulas and view their parse
tree