rmd_node_utilities: rmd node utility functions

In parsermd: Formal Parser and Related Tools for R Markdown Documents

rmd node utility functions

Description

Functions for extracting information for Rmd nodes.

Usage

rmd_node_label(x)

rmd_node_label(x) <- value

## Default S3 replacement method:
rmd_node_label(x) <- value

## S3 replacement method for class 'rmd_chunk'
rmd_node_label(x) <- value

rmd_node_type(x)

rmd_node_length(x)

rmd_node_content(x)

rmd_node_attr(x, attr)

rmd_node_engine(x)

rmd_node_options(x, yaml_style = TRUE)

rmd_node_code(x)

rmd_node_options(x) <- value

## Default S3 replacement method:
rmd_node_options(x) <- value

## S3 replacement method for class 'rmd_chunk'
rmd_node_options(x) <- value

rmd_node_attr(x, attr) <- value

## Default S3 replacement method:
rmd_node_attr(x, attr) <- value

## S3 replacement method for class 'rmd_node'
rmd_node_attr(x, attr) <- value

rmd_node_content(x) <- value

## Default S3 replacement method:
rmd_node_content(x) <- value

## S3 replacement method for class 'rmd_chunk'
rmd_node_content(x) <- value

## S3 replacement method for class 'rmd_raw_chunk'
rmd_node_content(x) <- value

## S3 replacement method for class 'rmd_markdown'
rmd_node_content(x) <- value

## S3 replacement method for class 'rmd_code_block'
rmd_node_content(x) <- value

## S3 replacement method for class 'rmd_code_block_literal'
rmd_node_content(x) <- value

rmd_node_set_label(x, value)

rmd_node_set_options(x, ...)

rmd_node_set_content(x, value)

rmd_node_set_attr(x, attr, value)

Arguments

x	An rmd object, e.g. rmd_ast or rmd_tibble.
value	The new value to assign (for assignment functions).
attr	Attribute name to extract or set.
yaml_style	logical, if TRUE (default) return option names in YAML style (with hyphens), if FALSE return normalized style (with dots)
...	For rmd_node_set_options(), named arguments that will be converted to a list of options to assign.

Value

• rmd_node_label() - returns a character vector of node labels, nodes without labels return NA.

• ⁠rmd_node_label<-()⁠ - assigns new labels to chunk nodes. For the setter, returns the modified object.

• rmd_node_type() - returns a character vector of node types.

• rmd_node_length() - returns an integer vector of node lengths (i.e. lines of code, lines of text, etc.), nodes without a length return NA.

• rmd_node_content() - returns the raw character vector(s) of node textual content (lines/code), nodes without content return NULL.

• rmd_node_attr() - returns the value of a given node attribute (S7 property), returns NULL if the attribute does not exist.

• rmd_node_engine() - returns a character vector of chunk engines, NA for all other node types.

• rmd_node_options() - returns a list of chunk node options (named list), NULL for all other node types. Option names are returned in YAML style (with hyphens) by default, or normalized style (with dots) if yaml_style = FALSE.

• ⁠rmd_node_options<-()⁠ - assigns new options to chunk nodes by merging with existing options. Takes a named list of options. For the setter, returns the modified object.

• ⁠rmd_node_attr<-()⁠ - assigns new attribute values to nodes. For the setter, returns the modified object.

• rmd_node_code() - returns a list of chunk node code (character vector), NULL for all other node types.

• rmd_node_set_label() - pipeable version of ⁠rmd_node_label<-()⁠ for setting node labels.

• rmd_node_set_options() - pipeable version of ⁠rmd_node_options<-()⁠ for setting chunk options.

• rmd_node_set_attr() - pipeable version of ⁠rmd_node_attr<-()⁠ for setting node attributes.

• ⁠rmd_node_content<-()⁠ - assigns new content to nodes. For the setter, returns the modified object.

• rmd_node_set_content() - pipeable version of ⁠rmd_node_content<-()⁠ for setting node content.

Examples

rmd = parse_rmd(system.file("examples/hw01.Rmd", package="parsermd"))

rmd_node_label(rmd)
rmd_node_type(rmd)
rmd_node_content(rmd)
rmd_node_attr(rmd, "level")
rmd_node_engine(rmd)
rmd_node_options(rmd)
rmd_node_code(rmd)

chunk = rmd_chunk("r", "example", code = "1 + 1")
rmd_node_label(chunk)
rmd_node_label(chunk) = "new_name"
rmd_node_label(chunk)

rmd_node_options(chunk) = list(eval = FALSE, echo = TRUE)
rmd_node_options(chunk)

rmd_node_attr(chunk, "engine") = "python"
rmd_node_attr(chunk, "engine")

rmd_node_content(chunk) = c("x = 2", "y = 3")
rmd_node_content(chunk)

chunk = rmd_chunk("r", "example", code = "1 + 1") |>
  rmd_node_set_label("new_label") |>
  rmd_node_set_options(eval = FALSE, echo = TRUE) |>
  rmd_node_set_content(c("a = 1", "b = 2"))

rmd_node_label(chunk)
rmd_node_options(chunk)
rmd_node_options(chunk, yaml_style = FALSE)  # get in normalized style
rmd_node_content(chunk)

chunk = rmd_chunk("r", "example", code = "x = 1") |>
  rmd_node_set_attr("engine", "python")

rmd_node_engine(chunk)

parsermd documentation built on Aug. 21, 2025, 5:27 p.m.