Turn environment list to a graph-CodePudding

I have a function that lists all the accessible environments in the current session.

env_list <- function(start_env) {
# convenience function
last <- function(s) { s[[length(s)]]}

res <- list(start_env)
while(!identical(emptyenv(), last(res))) {
res <- c(res, list(parent.env(last(res))))
}
res
}
env_list(globalenv())

The result i'm getting looks something like this:

[[1]]
<environment: R_GlobalEnv>

[[2]]
<environment: package:rlang>
attr(,"name")
[1] "package:rlang"
attr(,"path")
[1] "C:/Users/Documents/R/win-library/4.1/rlang"

[[3]]
<environment: package:igraph>
attr(,"name")
[1] "package:igraph"
attr(,"path")
[1] "C:/Users/Documents/R/win-library/4.1/igraph"

Could you advise approach to convert this list to a graph? I want to plot it with igraph later. Elements 1, 2, 3 probably should be nodes, but then what is the best way to denote edges, connecting parent and child environments?

CodePudding user response：

The obvious way to do this is to create an edgelist as a two-column character matrix with each environment's name in the left column, and its parent's name in the right column:

library(igraph)

my_envs <- env_list(globalenv())

edgelist <- t(sapply(my_envs[-length(my_envs)], function(x) {
   c(environmentName(x), environmentName(parent.env(x)))
}))

g <- graph_from_edgelist(edgelist)

plot(g)