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Record a GIF demo of an R expression

record_demo.Rd

Captures the unevaluated R expression expr, types it line-by-line into a freshly-spawned R session inside a vhs recording, and writes the result to output. The R front-end is chosen by backend (see below). Setup is a one-liner: if the required binaries are missing, the function points to vhsr_install().

Usage

record_demo(
  expr,
  output = "demo.gif",
  ...,
  backend = c("auto", "arf", "radian", "R"),
  tape = NULL,
  quiet = FALSE
)

Arguments

expr

An R expression (typically a { ... } block). Captured unevaluated; lines are typed verbatim into the REPL.

output

Path to the output file. The extension determines the format (.gif, .mp4, .webm).

...

Pacing and styling arguments forwarded to tape_options(). Pass any of width, height, font_size, theme, typing_speed, playback_speed, line_pause, start_pause, end_pause, paragraph_pause, typing_speed_jitter by name. Unknown names error.

backend

Which interactive R front-end to record. "auto" (the default) prefers "arf" (a Rust-based modern R console with tree-sitter syntax highlighting and zero runtime dependencies — see https://github.com/eitsupi/arf), falls back to "radian" if found, otherwise plain "R".

tape

Optional. A raw .tape script as a string (or path to a .tape file). When supplied, expr and the styling args are ignored and the tape is run verbatim.

quiet

If TRUE, suppress vhs stdout/stderr.

Value

Invisibly returns the path to the output file.

See also

tape_options() for the full pacing/styling argument list.

Examples

if (FALSE) { # \dontrun{
record_demo({
  x <- 1:5
  mean(x)
  head(cars, 3)
}, output = "demo.gif")
} # }