sxp: Inspect an object

In lobstr: Visualize R Data Structures with Trees

Inspect an object

Description

sxp(x) is similar to .Internal(inspect(x)), recursing into the C data structures underlying any R object. The main difference is the output is a little more compact, it recurses fully, and avoids getting stuck in infinite loops by using a depth-first search. It also returns a list that you can compute with, and carefully uses colour to highlight the most important details.

Usage

sxp(x, expand = character(), max_depth = 5L)

Arguments

x	Object to inspect
expand	Optionally, expand components of the true that are usually suppressed. Use: "character" to show underlying entries in the global string pool. "environment" to show the underlying hashtables. "altrep" to show the underlying data. "call" to show the full AST (but ast() is usually superior) "bytecode" to show generated bytecode.
max_depth	Maximum depth to recurse. Use max_depth = Inf (with care!) to recurse as deeply as possible. Skipped elements will be shown as ....'

Details

The name sxp comes from SEXP, the name of the C data structure that underlies all R objects.

See Also

Other object inspectors: ast(), ref()

Examples

x <- list(
  TRUE,
  1L,
  runif(100),
  "3"
)
sxp(x)

# Expand "character" to see underlying CHARSXP entries in the global
# string pool
x <- c("banana", "banana", "apple", "banana")
sxp(x)
sxp(x, expand = "character")

# Expand altrep to see underlying data
x <- 1:10
sxp(x)
sxp(x, expand = "altrep")

# Expand environmnets to see the underlying implementation details
e1 <- new.env(hash = FALSE, parent = emptyenv(), size = 3L)
e2 <- new.env(hash = TRUE, parent = emptyenv(), size = 3L)
e1$x <- e2$x <- 1:10

sxp(e1)
sxp(e1, expand = "environment")
sxp(e2, expand = "environment")

lobstr documentation built on June 23, 2022, 1:05 a.m.