R: Rd Utilities

Rdutils {tools}

R Documentation

Rd Utilities

Description

Utilities for computing on the information in Rd objects.

Usage

Rd_db(package, dir, lib.loc = NULL, stages = "build")

Arguments

`package`	a character string naming an installed package.
`dir`	a character string specifying the path to a package's root source directory. This should contain the subdirectory ‘man’ with R documentation sources (in Rd format). Only used if `package` is not given.
`lib.loc`	a character vector of directory names of R libraries, or `NULL`. The default value of `NULL` corresponds to all libraries currently known. The specified library trees are used to search for `package`.
`stages`	if `dir` is specified and the database is being built from source, which stages of `⁠\Sexpr⁠` processing should be processed?

Details

Rd_db builds a simple database of all Rd objects in a package, as a list of the results of running parse_Rd on the Rd source files in the package and processing platform conditionals and some ⁠\Sexpr⁠ macros.

Examples


## Build the Rd db for the (installed) base package.
db <- Rd_db("base")

## Keyword metadata per Rd object.
keywords <- lapply(db, tools:::.Rd_get_metadata, "keyword")
## Tabulate the keyword entries.
kw_table <- sort(table(unlist(keywords)))
## The 5 most frequent ones:
rev(kw_table)[1 : 5]
## The "most informative" ones:
kw_table[kw_table == 1]

## Concept metadata per Rd file.
concepts <- lapply(db, tools:::.Rd_get_metadata, "concept")
## How many files already have \concept metadata?
sum(sapply(concepts, length) > 0)
## How many concept entries altogether?
length(unlist(concepts))