gen_tag_functions: Function generator to simplify generation of 'XiMpLe_node'...

In XiMpLe: A Simple XML Tree Parser and Generator

Function generator to simplify generation of XiMpLe_node objects

Description

Takes a vector of character strings and turns them into functions in the defined environment which in turn will generate XiMpLe_node objects with the string values as tag names.

Usage

gen_tag_functions(
  tags,
  func_names = paste0(tags, "_"),
  envir = .GlobalEnv,
  replace = FALSE,
  func_rename = c(`?xml_` = "xml_", `!--_` = "comment_", `![CDATA[_` = "CDATA_",
    `!DOCTYPE_` = "DOCTYPE_")
)

Arguments

tags	A character vector defining the tags the generated functions should produce.
func_names	A character vector the same length as tags, defining the names of the functions to generate.
envir	The environment where all generated functions should appear.
replace	Logical, whether objects by the same name already present in envir should be preserved or replaced/overwritten.
func_rename	Named character vector defining which tags' functions should get a different name. This makes it easier to get functions with valid names that generate special tag nodes.

Details

The generated functions will be named according to func_names and only have a dots argument that is given to XMLNode. See the examples to understand how it's supposed to work.

Value

As many functions as specified by tags/func_names.

See Also

XMLNode,

Examples

# Say we would like to generate an HTML website and want to use
# <a>, <div> and <p> tags.
# The standard way of creating a <div> node would be this:
(my_node <- XMLNode("div", "some content", class="important"))

# By using gen_tag_functions(), we can create some shortcut functions
# to get better readability for our code and save some typing:
gen_tag_functions(tags=c("a", "div", "p"))
# We can now use div_() instead of XMLNode("div"):
(my_node2 <- div_("some content", class="important"))

# It also works for nested tags:
(my_node3 <- div_(a_(href="foo", "some content")))

# If you don't want these functions filling up your .GlobalEnv,
# you can also put them in an attached environment, e.g.
attach(list(), name="XiMpLe_wrappers")
gen_tag_functions(tags=c("head", "body"), envir=as.environment("XiMpLe_wrappers"))

XiMpLe documentation built on Aug. 22, 2023, 5:07 p.m.