library(felp)
library(printr) # To include documents output by `?` in this article

The felp package provides

  • the ?. pseudo-post fix operator to simultaneously display a help document and a structure of an object
  • the ?p pseudo-post fix operator to display document of a package
  • the felp function and ? operator to extend help and ? in the utils package by displaying structure of an object

Syntax

# ? as a prefix operator
?help
?utils::help

# ?. as a pseudo postfix operator for functions and objects
help?.
utils::help?.

# ?p as a pseudo postfix operator fur packages
utils?p

# felp as an extention of utils::help
felp(help)
felp("help")
felp(utils::help)
felp(help, utils)
felp(package = utils)

felp(function)

felp?. # and `felp(felp)` return source and document of `felp` function
function (topic, package = NULL, ...) 
{
    if (missing(topic)) 
        return(do.call(help, list(package = substitute(package), 
            ...)))
    t <- rev(as.character(substitute(topic)))
    p <- c(as.character(substitute(package)), t[2L])[1L]
    if (is.na(p)) 
        p <- NULL
    str(get(t[1L], envir = if (is.null(p)) 
        parent.frame()
    else asNamespace(p)))
    try(help(t[1L], p[1L], ...))
}
<bytecode: 0x55cf0756f348>
<environment: namespace:felp>
felp R Documentation

Functional help which displays structure of an object in addition to help

Description

Structure of object is returned by str(). For a function, its source is returned instead of str().

Usage

felp(topic, package = NULL, ...)

Arguments

topic

usually, a name or character string specifying the topic for which help is sought. A character string (enclosed in explicit single or double quotes) is always taken as naming a topic.

If the value of topic is a length-one character vector the topic is taken to be the value of the only element. Otherwise topic must be a name or a reserved word (if syntactically valid) or character string.

See ‘Details’ for what happens if this is omitted.

package

a name or character vector giving the packages to look into for documentation, or NULL. By default, all packages whose namespaces are loaded are used. To avoid a name being deparsed use e.g. (pkg_ref) (see the examples).

Arguments passed on to utils::help

lib.loc

a character vector of directory names of R libraries, or NULL. The default value of NULL corresponds to all libraries currently known. If the default is used, the loaded packages are searched before the libraries. This is not used for HTML help (see ‘Details’).

verbose

logical; if TRUE, the file name is reported.

try.all.packages

logical; see Note.

help_type

character string: the type of help required. Possible values are “text”, “html” and “pdf”. Case is ignored, and partial matching is allowed.

Examples

# Identical to help(identity); print(identity)
felp(identity)

# Identical to help(iris); str(iris)
felp(iris)

# Identical to help(package = MASS)
felp(package = MASS)


felp(dataset)

dummy?. # and `felp(dummy)` return sructure and document of `dummy` dataset.
List of 2
 $ a: chr "a"
 $ b: num 1
dummy R Documentation

A dummy data for felp

Description

A dummy data for felp

Usage

dummy

Format

An object of class list of length 2.

felp(package)

felp?p # and `felp(package = felp)` return document of `felp` package
        Information on package 'felp'

Description:

Package:            felp
Type:               Package
Title:              Functional Help for Functions, Objects, and
                    Packages
Version:            0.2.1
Author:             Atsushi Yasumoto [aut, cph, cre]
                    (<https://orcid.org/0000-0002-8335-495X>)
Authors@R:          c( person( given = "Atsushi", family =
                    "Yasumoto", role = c("aut", "cph", "cre"),
                    email = "atusy.rpkg@gmail.com", comment =
                    c(ORCID = "0000-0002-8335-495X") ) )
Maintainer:         Atsushi Yasumoto <atusy.rpkg@gmail.com>
Description:        Provides pseudo-postfix operators and more to
                    enhance displaying documents.  The `?.`
                    pseudo-postfix operator and the `?` prefix
                    operator displays documents and contents
                    (source or structure) of objects
                    simultaneously to help understanding the
                    objects.  The `?p` pseudo-postfix operator
                    displays package documents, and is shorter
                    than help(package = foo).
URL:                https://github.com/atusy/felp
BugReports:         https://github.com/atusy/felp/issues
License:            MIT + file LICENSE
Encoding:           UTF-8
LazyData:           true
Roxygen:            list(markdown = TRUE)
RoxygenNote:        6.1.1
Imports:            prettycode
Suggests:           knitr, pkgdown, printr, rmarkdown, roxygen2,
                    testthat (>= 2.1.0), covr
VignetteBuilder:    knitr
Language:           en-US
RemoteType:         github
RemoteHost:         api.github.com
RemoteRepo:         felp
RemoteUsername:     atusy
RemoteRef:          master
RemoteSha:          671d4c32d6b6efd76fae2bc763340f14780bf99b
GithubRepo:         felp
GithubUsername:     atusy
GithubRef:          master
GithubSHA1:         671d4c32d6b6efd76fae2bc763340f14780bf99b
NeedsCompilation:   no
Packaged:           2019-06-28 06:17:57 UTC; root
Built:              R 3.6.0; ; 2019-06-28 06:17:58 UTC; unix

Index:

?                       Functional help with '?' operator
dummy                   A dummy data for felp
felp                    Functional help which displays structure of an
                        object in addition to help