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Set knitr Hooks for ANSI Aware HTML Output

Source: R/ansi_set_knit_hooks.R
ansi_set_knit_hooks.Rd

Configures knitr output hooks to convert ANSI sequences to HTML. This enables styled cli output to render correctly in HTML documents produced by knitr, R Markdown, or Quarto.

Usage

ansi_set_knit_hooks(
  hooks,
  which = c("output", "message", "warning", "error"),
  class = "ansi",
  style = TRUE,
  collapse = TRUE,
  palette = "vscode",
  colors = 256,
  preserve_newlines = FALSE
)

Arguments

hooks

The knitr::knit_hooks object.

which

Character vector of hooks to replace. Defaults to c("output", "message", "warning", "error").

class

Character vector of CSS classes for output blocks, recycled to match which. Defaults to "ansi".

style

Whether to emit CSS styles from cli::ansi_html_style(). Defaults to TRUE.

collapse

Whether to emit CSS to remove margins between consecutive output blocks. Defaults to TRUE.

palette

Palette for cli::ansi_html_style(). Defaults to "vscode".

colors

Number of ANSI colors to set via cli::num_ansi_colors(). Defaults to 256. Set to NULL to leave unchanged.

preserve_newlines

Whether to convert newlines to <br> tags to ensure they are preserved in the HTML output. Defaults to FALSE. Set to TRUE if your output is missing line breaks.

Value

Invisibly returns the previous hooks as a named list.

Details

The hook only processes output containing ANSI sequences (detected via cli::ansi_has_any()). Other output is passed to the original hook unchanged.

For non-HTML output formats, ANSI sequences are stripped via cli::ansi_strip().

See also

cli::ansi_html(), cli::ansi_html_style(), cli::ansi_strip()