Package 'regexplain'

Title: Rstudio Addin to Explain, Test and Build Regular Expressions
Description: A set of RStudio Addins to help interactively test and build regular expressions. Provides a Shiny gadget interface for interactively constructing the regular expression and viewing the results from common string-searching functions. The gadget interface includes a helpful regex syntax reference sheet and a library of common patterns.
Authors: Garrick Aden-Buie [aut, cre], Winston Chang [ctb] (Author of textInput and textAreaInput fragments from shiny), Yihui Xie [ctb] (Author of escape_html fragment from highr), RStudio [cph] (Copyright holder of included shiny fragments)
Maintainer: Garrick Aden-Buie <[email protected]>
License: GPL-3
Version: 0.2.2.9000
Built: 2024-08-11 02:48:51 UTC
Source: https://github.com/gadenbuie/regexplain

Help Index

Extract matched groups from regexp

Description

Extract matched groups from regexp

Usage

regex(
  text,
  pattern,
  ignore.case = FALSE,
  perl = FALSE,
  fixed = FALSE,
  useBytes = FALSE,
  global = TRUE
)

Arguments

text

Text to search
pattern

regexp
ignore.case

if FALSE, the pattern matching is case sensitive and if TRUE, case is ignored during matching.
perl

logical. Should Perl-compatible regexps be used?
fixed

logical. If TRUE, pattern is a string to be matched as is. Overrides all conflicting arguments.
useBytes

logical. If TRUE the matching is done byte-by-byte rather than character-by-character. See ‘Details’.
global

If TRUE, enables global pattern matching

Regex Cheatsheet Quick Reference

Description

The function behind the RegExplain Cheatsheet addin. Opens a summary of regular expression syntax – the RegExplain cheatsheet – in an RStudio viewer pane.

Usage

regexplain_cheatsheet()

RegExplain gadget

Description

The function behind the RegExplain Selection and RegExplain File addins. Opens the RegExplain gadget interface in an RStudio viewer pane.

Usage

regexplain_file(pattern = NULL, start_page = "RegEx")

regexplain_gadget(
  text = NULL,
  pattern = NULL,
  start_page = if (is.null(text)) "Text" else "RegEx"
)

regexplain_web(text = NULL, pattern = NULL, start_page = "Text", ...)

Arguments

pattern

Regular Expression to edit or visualize using RegExplain
start_page

Open gadget to this tab, one of "Text", "RegEx", "Output", or "Help"
text

Text to explore in gadget (editable using interface)
...

Arguments passed on to shiny::shinyApp

ui

The UI definition of the app (for example, a call to fluidPage() with nested controls)

server

A function with three parameters: input, output, and session. The function is called once for each session ensuring that each app is independent.

onStart

A function that will be called before the app is actually run. This is only needed for shinyAppObj, since in the shinyAppDir case, a global.R file can be used for this purpose.

options

Named options that should be passed to the runApp call (these can be any of the following: "port", "launch.browser", "host", "quiet", "display.mode" and "test.mode"). You can also specify width and height parameters which provide a hint to the embedding environment about the ideal height/width for the app.

uiPattern

A regular expression that will be applied to each GET request to determine whether the ui should be used to handle the request. Note that the entire request path must match the regular expression in order for the match to be considered successful.

enableBookmarking

Can be one of "url", "server", or "disable". This is equivalent to calling the enableBookmarking() function just before calling shinyApp(). With the default value (NULL), the app will respect the setting from any previous calls to enableBookmarking(). See enableBookmarking() for more information.

Value

The regular expression built in the app is returned as a character string.

Functions

  • regexplain_file: Opens file chooser to pick file, reads lines, returns first regexplain.addin.max_lines (default 100). Used in the "Regexplain File" regexplain_addin.

  • regexplain_web: Launches the RegExplain gadget in a browser or an RStduio viewer pane.

Examples

## Not run: 
regexplain_gadget(text = month.name, pattern = "(Ma|Ju)|(er)")
regexplain_web(text = month.name, pattern = "(Ma|Ju)|(er)")
regexplain_file()

## End(Not run)

Modified Text Area Input

Description

Standard shiny::textAreaInput() with additional is_code parameter, added code font style for the input text and with autocomplete, autocorrect, autocapitalize and spellcheck set to off or false.

Usage

textAreaInputAlt(
  inputId,
  label,
  value = "",
  width = NULL,
  height = NULL,
  cols = NULL,
  rows = NULL,
  placeholder = NULL,
  resize = NULL,
  is_code = TRUE
)

Arguments

inputId

The input slot that will be used to access the value.
label

Display label for the control, or NULL for no label.
value

Initial value.
width

The width of the input, e.g. '400px', or '100%'; see validateCssUnit().
height

The height of the input, e.g. '400px', or '100%'; see validateCssUnit().
cols

Value of the visible character columns of the input, e.g. 80. This argument will only take effect if there is not a CSS width rule defined for this element; such a rule could come from the width argument of this function or from a containing page layout such as fluidPage().
rows

The value of the visible character rows of the input, e.g. 6. If the height argument is specified, height will take precedence in the browser's rendering.
placeholder

A character string giving the user a hint as to what can be entered into the control. Internet Explorer 8 and 9 do not support this option.
resize

Which directions the textarea box can be resized. Can be one of "both", "none", "vertical", and "horizontal". The default, NULL, will use the client browser's default setting for resizing textareas.
is_code

Should the text input be considered verbatim code input?

See Also

Other modified shiny inputs: textInputCode()

Modified Text Input

Description

Standard shiny::textInput() with additional width parameter, added code font style for the input text and with autocomplete, autocorrect, autocapitalize and spellcheck set to off or false.

Usage

textInputCode(
  inputId,
  label,
  value = "",
  width = NULL,
  placeholder = NULL,
  ...
)

Arguments

inputId

The input slot that will be used to access the value.
label

Display label for the control, or NULL for no label.
value

Initial value.
width

Width of shiny-input-container div.
placeholder

A character string giving the user a hint as to what can be entered into the control. Internet Explorer 8 and 9 do not support this option.
...

Extra elements to be included in the input-group div.

See Also

Other modified shiny inputs: textAreaInputAlt()

View grouped regex results

Description

View the result of the regular expression when applied to the given text. The default behavior renders the result as HTML and opens the file in the RStudio viewer pane. If render is FALSE, the HTML itself is returned. If the output is destined for a knitr document, set knitr to TRUE.

Usage

view_regex(
  text,
  pattern,
  ...,
  render = TRUE,
  escape = render,
  exact = escape,
  result_only = FALSE
)

Arguments

text

Text to search
pattern

Regex pattern to look for
...

Arguments passed on to base::regexec

ignore.case

if FALSE, the pattern matching is case sensitive and if TRUE, case is ignored during matching.

perl

logical. Should Perl-compatible regexps be used?

fixed

logical. If TRUE, pattern is a string to be matched as is. Overrides all conflicting arguments.

useBytes

logical. If TRUE the matching is done byte-by-byte rather than character-by-character. See ‘Details’.
render

Render results as HTML?
escape

Escape HTML-related characters in text?
exact

Should the regex pattern be displayed as entered by the user into R console or source (default)? When TRUE, regex is displayed with the double ⁠\\\\⁠ required for escaping backslashes in R. When FALSE, regex is displayed as interpreted by the regex engine (i.e. double ⁠\\\\⁠ as a single ⁠\\⁠).
result_only

Should only the result be displayed? If FALSE, then the colorized regular expression is also displayed in the output.

Examples

view_regex("example", "amp", render = FALSE)