typeR: Simulate Typing Script

Description

Simulates typing of R script files for presentations and demonstrations. Provides character-by-character animation with optional live code execution. Supports R scripts (.R), R Markdown (.Rmd), and Quarto (.qmd) documents.

Author(s)

Maintainer: Federica Gazzelloni fede.gazzelloni@gmail.com

See Also

Useful links:

• https://Fgazzelloni.github.io/typeR/

• https://github.com/Fgazzelloni/typeR

• Report bugs at https://github.com/Fgazzelloni/typeR/issues

Simulate Typing of an R Script File

Description

Simulates typing out the content of an R script file, line by line, character by character, to create an animation effect for live coding presentations or educational demonstrations.

Usage

typeR(file, delay = 0.05)

Arguments

Value

Invisibly returns NULL. Called for the side effect of displaying typed content in the console with animation.

Examples

# Create a temporary R script for demonstration
tmp <- tempfile(fileext = ".R")
writeLines(c(
  "# Example R script",
  "x <- 1:10",
  "mean(x)"
), tmp)

# Simulate typing the script (fast for testing)
typeR(tmp, delay = 0.01)

# Clean up
unlink(tmp)

# Longer example with realistic typing speed

  tmp2 <- tempfile(fileext = ".R")
  writeLines(c(
    "# Data analysis example",
    "data <- mtcars",
    "model <- lm(mpg ~ wt, data = data)",
    "summary(model)"
  ), tmp2)
  typeR(tmp2, delay = 0.08)
  unlink(tmp2)

Type and Run R Code with Live Evaluation

Description

An enhanced version of typeR that not only simulates typing but also evaluates R code in real-time. Supports interactive pause/resume control and handles both Quarto/R Markdown documents and plain R scripts.

Usage

typeRun(
  file,
  delay = 0.05,
  jitter = 0.01,
  max_print = 10,
  envir = new.env(parent = .GlobalEnv)
)

Arguments

Details

typeRun() extends the basic typeR() functionality by:

• Live Code Evaluation: Executes R code chunks as they are typed

• Interactive Control: Press ESC/Ctrl+C to pause, then choose to resume or stop

• Smart Output: Truncates long outputs and handles models intelligently

• Format Support: Handles .R, .Rmd, and .qmd files intelligently

For Quarto/R Markdown files, typeRun():

• Skips YAML headers

• Only evaluates code in R code chunks

• Preserves narrative text without evaluation

For R scripts, it evaluates all non-comment, non-empty lines.

Value

Invisibly returns NULL. Called for side effects (typing animation and code evaluation).

Output Handling

• Assignments and plotting functions execute silently

• Long vectors/data frames are truncated to max_print elements

• Model summaries (lm, glm, etc.) display using R's standard print methods

• Raw model objects (without summary call) show a simple fitted message

• Package loading messages (library/require) are suppressed

• Errors are caught and displayed without stopping execution

Interactive Control

During execution, you can:

1. Press ESC (or Ctrl+C on some systems) to pause

2. Enter 1 to resume from where you paused

3. Enter 2 to stop completely

See Also

typeR for typing without evaluation

Examples

# Create a temporary R script for demonstration
tmp <- tempfile(fileext = ".R")
writeLines(c(
  "# Simple calculation",
  "x <- 1:5",
  "print(mean(x))",
  "y <- x^2",
  "print(sum(y))"
), tmp)

# Type and run with fast animation (for quick testing)

  typeRun(tmp, delay = 0.01, max_print = 5)


# Clean up
unlink(tmp)

# Interactive examples with real files
if (interactive()) {
  # Type and run a simple R script
  typeRun("analysis.R")

  # Type and run with slower, more dramatic effect
  typeRun("demo.R", delay = 0.1, jitter = 0.02)

  # Type and run a Quarto document with limited output
  typeRun("report.qmd", max_print = 5)
}