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App::Rak zef:lizmat last updated on 2022-12-01

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NAME

App::Rak - 21st century grep / find / ack / ag / rg on steroids

SYNOPSIS

# look for "foo" in current directory recursively
$ rak foo

# look for "foo" in directory "bar" recursively
$ rak foo bar

# look for "foo" as word in current directory
$ rak '/ << foo >> /'

# look for "foo", only produce filenames
$ rak foo --files-with-matches

# also produce 2 lines before and after
$ rak foo --before=2 --after=2

# lines with foo AND bar
$ rak '{.contains("foo") && .contains("bar")}'

DESCRIPTION

App::Rak provides a CLI called rak that allows you to look for a pattern in (a selection of files) from one or more directories recursively. It has been modelled after utilities such as grep, ack, ag and rg, with a little bit of find mixed in, and -n and -p parameters of many programming languages.

Note: this project is now in beta-development phase. Comments, suggestions and bug reports continue to be more than welcome!

POSITIONAL ARGUMENTS

pattern

The pattern to search for.

Can also be specified with the --pattern option, in which case all the positional arguments are considered to be a path specification.

Patterns will be interpreted in the following ways if no --type has been specified, or --type=auto has been specified.

Multiple patterns, stored in a file or read from STDIN, can also be specified with the argument.

/ regex /

If the pattern starts and ends with /, then it indicates a Raku regex. No special processing of the given string between slashes will be done: the given pattern will be parsed as a regex verbatim. During the search process, each item will be matched against this regex. Any --ignorecase or --ignoremark arguments will be honoured.

{ code }

If the pattern starts with { and ends with }, then it indicates Raku code to be executed. No special processing of the given string between the curly braces will be done: the given code will be compiled as Raku code. During the search process, this code will be run for each item, available in $_. To facilitate the use of libraries that wish to access that topic, it is also available as the $*_ dynamic variable.

The dynamic variable $*SOURCE will contain the IO::Path object of the file being processed. Note that the Raku code will be called in a thread unsafe manner.

The dynamic variable $*_ will contain the topic with which the code was called. This to allow custom libraries to easily obtain the topic without the user needing to specify that again.

*code

If the pattern starts with *, then this is a short way of specifying Raku code as a pattern, using Whatever-currying. Otherwise the same as { code }.

jp:path

If the pattern start with 'jp:', then interpret the rest of the pattern as a JSON path. Only makes sense when used together with --json-per-file, --json-per-line or --json-per-elem. Requires that the JSON::Path module is installed. Basically a shortcut to specifying path --type=json-path.

Supported JSON path syntax

$           root node
.key        index hash key
['key']     index hash key
[2]         index array element
[0,1]       index array slice
[4:5]       index array range
[:5]        index from the beginning
[-3:]       index to the end
.*          index all elements
[*]         index all elements
[?(expr)]   filter on Raku expression
..key       search all descendants for hash key

A query that is not rooted from $ or specified using .. will be evaluated from the document root (that is, same as an explicit $ at the start).

Full Raku support

The jp:path and --type=json-path syntax are actually syntactic sugar for calling a dedicated jp macro that takes an unquoted JSON path as its argument, and returns an instantiated JP object.

This means that:

$ rak --json-per-file jp:foo
$ rak --json-per-file --type=json-path foo

are a different way of saying:

$ rak --json-per-file '{ jp(path).Slip }'

using the "pattern is Raku code" syntax.

The following methods can be called on the JP object:

.value             The first selected value.
.values            All selected values as a Seq.
.paths             The paths of all selected values as a Seq.
.paths-and-values  Interleaved selected paths and values.

Without listing all of the methods that can be called on the JP object, one should note that all efforts have been made to make the JP object act like a Seq.

^string

If the pattern starts with ^, then it indicates the string should be at the start of each item. Basically a shortcut to specifying string --type=starts-with. Any --smartcase, --smartmark, --ignorecase or --ignoremark arguments will be honoured.

string$

If the pattern ends with $, then it indicates the string should be at the end of each item. Basically a shortcut to specifying string --type=ends-with. Any --smartcase, --smartmark, --ignorecase or --ignoremark arguments will be honoured.

^string$

If the pattern starts with ^ and ends with $, then it indicates that the string should be equal to the item. Basically a shortcut to specifying string --type=equal. Any --smartcase, --ignorecase or --ignoremark arguments will be honoured.

§string

If the pattern starts with §, then it indicates that the string should occur as a word (with word-boundaris on both ends) in the item. Basically a shortcut to specifying string --type=words. Any --smartcase, --smartmark, --ignorecase or --ignoremark arguments will be honoured.

string

If there are no special start or end markers, then it indicates that the string should occur somewhere in the item. Basically a shortcut to specifying string --type=contains. Any --smartcase, --smartmark, --ignorecase or --ignoremark arguments will be honoured.

path(s)

Optional. Either indicates the path of the directory (and its sub-directories), or the file that will be searched, or a URL that will produce a file to be searched. By default, all directories that do not start with a period, and which are not symbolic links, will be recursed into (but this can be changed with the --dir option).

By default, all files with known extensions will be searched in the directories. This can be changed with the --file option, or specialized version of that like --extensions.

Paths can also be specified with the --paths option, in which case there should only be a positional argument for the pattern, or none if --pattern option was used for the pattern specification.

ON CALLABLES AS PATTERN

Callables can be specified by a string starting with *. (so-called Whatever currying, or as a string starting with { and ending with }.

Note that if a Callable is specified as a pattern, then no highlighting can be performed as it cannot signal why or where a match occurred.

The return value of the pattern Callable match is interpreted in the following way:

True

If the Boolean True value is returned, assume the pattern is found. Produce the item unless --invert-match was specified.

False

If the Boolean False value is returned, assume the pattern is not found. Do not produce the item unless --invert-match was specified.

Nil

If Nil is returned, assume the pattern is not found.

This typically happens when a try is used in a pattern, and an execution error occurred. Do not produce the item unless --invert-match was specified.

Empty

If the empty Slip is returned, assume the pattern is not found. Do not produce the item unless --invert-match was specified. Shown in stats as a passthru.

any other Slip

If a non-empty Slip is returned, produce the values of the Slip separately for the given item (each with the same item number).

any other value

Produce that value.

PHASERS IN CALLABLE PATTERNS

The Raku Programming Language has a number of unique features that can be used with patterns that are executable code. One of them is the use of so-called phasers (pieces of code that will be executed automatically when a certain condition has been met.

App::Rak currently supports all of Raku's loop phasers:

These phasers will be called in a thread-safe manner.

# show number of files inspected before the search result
$ rak '{ state $s = 0; NEXT $s++; LAST say "$s files"; .contains("foo")}'

# show number of files inspected after of the search result
$ rak '{ state $s = 0; NEXT $s++; END say "$s files"; .contains("foo")}'

Note that the use of the LAST phaser will make the search run eagerly, meaning that no results will be shown until the search has been completed.

Any other phasers that do not require special attention by App::Rak are also supported in any code specified (such as BEGIN and END).

ON THE INTERPRETATION OF OPTIONS

All options when using App::Rak, start with either one dash - or two dashes --.

If an option starts with two dashes, it is a so-called "long option". Any characters after the dashes are considered to be the single name of the option.

If an option starts with a single dash, then it is considered to be a collection of "short options", each of 1 letter. If the number of short options is 1, then it can be followed by a numerical value (without equal sign).

If the specification of the option does not contain an equal sign =, then the option is interpreted as a boolean option. By default, such a flag is considered to represent True. The value can be negated in two ways:

Some examples:

Option "i" is True.

Option "j" has the value 5.

Options "i" and "m" are True.

Option "i" is False.

Options "i" and "m" are False.

Option "i" is False.

Option "foo" is True.

Option "foo" is False.

Option "foo" is False.

If the specification of an option contains an equal sign after the name, then whatever follows that, is considered the value of that option. Whether or not that value needs to be quoted, and how they are to be quoted, really depends on the shell that you use to access rak. Generally, if the value consists of alphanumeric characters only, no quoting is necessary. Otherwise it's better to quote your values.

Some examples:

Option "s" has the value "foo".

Option "t" has the value "foo bar".

Option "frobnicate" has the value "yes".

CREATING YOUR OWN OPTIONS

App::Rak provides many options. If you are happy with a set of options for a certain workflow, You can use the --save option to save that set of options and than later access them with the given name:

# create -i shortcut for ignoring case
$ rak --ignorecase --save=i
Saved option '-i' as: --ignorecase

# create -m shortcut for ignoring accents
$ rak --ignoremark --save=m
Saved option '-m' as: --ignoremark

# same as --ignorecase --ignoremark
$ rak foo -im

Generally speaking, the most used boolean options can be saved as single letter options: this allows multiple options to be specified in a single, short manner (as shown above).

To better document / remember what a particular custom option is meant to do, you can add a description with the --description option.

# add a description to the -i custom option
$ rak --description='Search without caring for uppercase' --save=i
Saved '--description='Search without caring for uppercase'' as: -i

# add an option -g for searching only git files
$ rak --description='Committed files only' --under-version-control --save=g
Saved '--description='Committed files only' --under-version-control' as: -g

There is also a special named option that indicates the options that will be automatically activated on any invocation: (default).

# enable --smartcase by default on every run
$ rak --smartcase --save='(default)'
Saved '--smartcase' as: (default)

You can use the --list-custom-options to see what options you have saved before.

Custom options are saved in ~/.rak-config.json. You can override this by specifying the RAK_CONFIG environment variable.

# read custom options from ".custom.json" (in the current directory)
$ RAK_CONFIG=.custom.json rak foo

You can also use the RAK_CONFIG variable to disable loading any configuration by not specifying a value:

# start rak without any custom configuration
$ RAK_CONFIG= rak foo

SUPPORTED OPTIONS

All options are optional. Any unexpected options, will cause an exception to be thrown with the unexpected options listed and possible alternatives mentioned. Unless specifically indicated otherwise, using the negation of a flag has the same effect as not specifying it.

--absolute

Flag. If specified indicates that whenever paths are shown, they will be shown as absolute paths. Defaults to False, which will cause paths to be produced as paths relative to the current directory.

--accept=code

Specifies the code that should be executed that should return True if the path is acceptable, given an IO::Path object of the path. See also --deny.

# Include files that have "use Test" in them
$ rak --accept='*.slurp.contains("use Test")'

--accessed=condition

If specified, indicates the Callable that should return True to include a file in the selection of files to be checked. The access time of the file (number of seconds since epoch, as a Num value) will be passed as the only argument. Note that many file systems do not actually support this reliably.

See "CHECKING TIMES ON FILES" for more information about features that can be used inside the Callable.

--after-context=N

Indicate the number of lines that should be shown after any line that matches. Defaults to 0. Will be overridden by a --context argument.

--allow-loose-escapes

Only applicable if --csv-per-line has been specified. Flag. If specified, indicates that any character may be escaped.

--allow-loose-quotes

Only applicable if --csv-per-line has been specified. Flag. If specified, indicates that fields do not need to be quoted to be acceptable.

--allow-whitespace

Only applicable if --csv-per-line has been specified. Flag. If specified, indicates that whitespace is allowed around separators.

--auto-decompress

Flag. If specified with a True value, will accept compressed files with the .gz (gzip) or .bz2 (bzip2) extension, if the extension was otherwise acceptable. Will automatically decompress files for inspection.

--auto-diag

Only applicable if --csv-per-line has been specified. Flag. If (implicitly) specified, will show diagnostic information about problems that occurred during parsing of the CSV file. The default is True.

--backtrace

Flag. When specified with a True value, will interpret either standard input, or a single file, as a Raku backtrace. And produce a result containing the lines of source code from that backtrace. Can be used together with --context, --before-context, --after-context, --edit and --vimgrep. Any pattern specification will only be used for highlighting. If not used in combination with --edit or --vimgrep, will assume a context of 2 lines.

# look at source of a stacktrace
$ raku script 2>&1 | rak --backtrace

# inspect the source of a stacktrace in an editor
$ raku script 2>&1 | rak --backtrace --edit

# inspect a backtrace stored in a file
$ rak --backtrace filename

--backup[=extension]

Indicate whether backups should be made of files that are being modified. If specified without extension, the extension .bak will be used.

--batch[=N]

Indicate the number of files that should be checked per thread. If specified as a flag, will assue 1. Defaults to 64 if not specified. See also <--degree>.

--before-context=N

Indicate the number of lines that should be shown before any line that matches. Defaults to 0. Will be overridden by a --context argument.

--blame-per-file

Flag. Only makes sense if the pattern is a Callable. If specified, indicates that each of the selected files will be provided as Git::Blame::File objects if git blame can be performed on the a selected file. If that is not possible, then the selected file will be ignored.

If information can be obtained, then the associated Git::Blame::File object will be presented to the pattern Callable. If the Callable returns True, then the filename will be produced. If anything else is returned, then the stringification of that object will be produced.

# show files with more than 10 commits
$ rak '*.commits > 10' --blame-per-file --files-with-matches

Requires that the Git::Blame::File module is installed.

--blame-per-line

Flag. Only makes sense if the pattern is a Callable. If specified, indicates that each line from the selected files will be provided as Git::Blame::Line objects if git blame can be performed on the a selected file. If that is not possible, then the selected file will be ignored.

If information can be obtained, then the associated Git::Blame::Line object will be presented to the pattern Callable. If the Callable returns True, then the short representation of the git blame information will be produced. If the returned value is anything else, then the stringification of that object will be produced.

# show git blame on lines of which the author is "Scooby Doo"
$ rak '{ .author eq "Scooby Doo" }' --blame-per-line

Requires that the Git::Blame::File module is installed.

--blocks=condition

If specified, indicates the Callable that should return True to include a file in the selection of files to be checked. The number of logical blocks that a file takes up in the filesystem, will be passed as the only argument.

# show files that consist of at least 3 blocks
$ rak --find --blocks='* >= 3'

--break[=string]

Indicate whether there should be a visible division between matches of different files. Can also be specified as a string to be used as the divider. Defaults to True (using an empty line as a divider) if --group-matches is (implicitly) set to True, else defaults to False.

--checkout=branch

Only valid if the current directory is under git version control. Indicate the branch to checkout by the general matching logic of App::Rak. Will produce listing of matching branches if more than one, or say that there is no match. Branches need not have been checked out locally yet.

--categorize=categorizer

If specified, indicates the Callable that should return zero or more keys for a given line to have it categorized. This effectively replaces the filename if a line by its key in the result. See also --classify.

# categorize by the first two letters of a line
$ rak --categorize='*.substr(0,2).comb'

--classify=classifier

If specified, indicates the Callable that should return a key for a given line to have it classified. This effectively replaces the filename if a line by its key in the result. See also --categorize.

# classify by the last letter of a line
$ rak --classify='*.substr(*-1)'

--context=N

Indicate the number of lines that should be produced around any line that matches. Defaults to 0.

--count-only

Flag. Indicate whether just the number of lines with matches should be calculated. When specified with a True value, will show a "N matches in M files" by default, and if the :files-with-matches (or files-without matches) option is also specified with a True value, will just show total counts. See also --stats-only.

--created=condition

If specified, indicates the Callable that should return True to include a file in the selection of files to be checked. The creation time of the file (number of seconds since epoch, as a Num value) will be passed as the only argument.

See "CHECKING TIMES ON FILES" for more information about features that can be used inside the Callable.

--csv-per-line

Flag. Only makes sense if the pattern is a Callable. If specified with a True value, indicates that selected files should be interpreted as comma separated values (CSV). Each row from the selected files will be provided as a list of strings (or as CSV::Field objects if --keep-meta was specified).

Attempt to interpret file as a CSV file, and pass each row as a List to to the pattern Callable. Only files with extensions from the #csv group will be tried, unless overridden by any explicit extension specification.

More documentation can be found with the Text::CSV module itself.

# Show the values of the column named "foo" of the rows in the "info.csv"
# file if the column named "bar" is equal to "foo"
$ rak --csv-per-line '{.<foo> if .<bar> eq "foo"}' info.csv

# Show the values of the first column of the rows in the "info.csv" file
# if the second column is equal to "foo"
$ rak --csv-per-line --/headers '{.[0] if .[1] eq "foo"}' info.csv

--degree[=N | code]

Indicate the number of worker threads that should be maximally. Defaults to the number of cores minus 1 if not specified. Assumes 1 if specified as a flag. Can also take a Callable specification, in which case the number of CPU cores will be presented to that Callable as the only argument. See also <--batch>.

--deny=code

Specifies the code that should be executed that should return True if the path is NOT acceptable, given an IO::Path object of the path. See also --accept.

# Include files that **NOT** have "use Test" in them
$ rak --deny='*.slurp.contains("use Test")'

--description=text

Specify a description to be saved with the custom option. This will be shown prominently with --list-custom-options. If it is the only argument apart from --save, then the discription will be added (if there was no description yet) or replace the current description of the option.

--device-number=condition

If specified, indicates the Callable that should return True to include a file in the selection of files to be checked. The device number of the filesystem on which the file is located, will be passed as the only argument.

--dir=condition

If specified, indicates the Callable that should return True to have a directory be included for further recursions in file selection. The basename of the directory will be passed as the only argument. Defaults to all directories that do not start with a period. Can specify as a flag to include all directories for recursion.

--dont-catch

Flag. If specified as a flag, will not catch any error during processing, but will throw any error again. Defaults to False, making sure that errors will be caught. Mainly intended for debugging and error reporting.

--dryrun

Flag. Indicate to not actually make any changes to any content modification if specified with a True value. Only makes sense together with the --modify-files and the --rename-files option.

--ecosystem[=name1,name2]

Intended to be used by Raku ecosystem maintainers. Indicates the name of zero or more Raku ecosystems of which to inspect the META6.json information of all its modules. Currently supported names are:

Defaults to rea if specified as a flag. Implies --json-per-elem.

# show all unique module names by an author from the REA
$ rak '{ .author eq "Scooby Doo" }' --ecosystem

# same, but now from the p6c and cpan ecosystems
$ rak '{ .author eq "Scooby Doo" }' --ecosystem=p6c,cpan

Assumes zef is installed and its meta information is available.

--edit[=editor]

Indicate whether the patterns found should be fed into an editor for inspection and/or changes. Defaults to False. Optionally takes the name of the editor to be used. If no editor is specified, will use what is in the EDITOR environment variable. If that is not specified either, will call "vim".

--eol=lf|cr|crlf

Only applicable if --csv-per-line has been specified. Indicate a line ending different from the standard line ending assumed by the system. Can be specified as lf for a single LineFeed character, cr for a single CarriageReturn character, or crlf for a combination of a CarriageReturn and a LineFeed character.

--escape=char

Only applicable if --csv-per-line has been specified. Indicates the escape character to be used to escape characters in a field. Defaults to double quote.

--exec=invocation

If specified, indicates the name of a program and its arguments to be executed. Any $_ in the invocation string will be replaced by the file being checked. The file will be included if the program runs to a successful conclusion.

--execute-raku[=code]

Flag or code specification. When specified with a True value, will use the pattern as the name of a script to execute. If code is specified will execute that code. If the code consists of "-", then will read code from STDIN to execute. Any execution error's backtrace will be used to produce a result with the lines of source code of that backtrace.

Can be used together with --context, --before-context, --after-context, --edit and --vimgrep. Will assume a context of 2 lines if not used in combination with --edit or --vimgrep,

If --verbose is specified, will try to create an extended (--ll-exception) backtrace.

# look at source of a stacktrace after running script
$ rak --execute-raku script

# inspect the source of a stacktrace in an editor
$ rak --execute-raku script --edit

# inspect a backtrace from execution of code read from STDIN
$ cat script | rak --execute-raku=-

--extensions=spec

Indicate the extensions of the filenames that should be inspected. By default, only files with known extensions, will be searched.

Extensions can be specified as a comma-separated list of either a a predefined group of extensions (indicated by #name), a single extension, or * to indicate all known extensions.

# inspect files with extensions used by Raku and Perl
$ rak foo --extensions=#raku,#perl

# inspect files with presumable Markdown content
$ rak foo --extensions=md,markdown

# inspect files without extension
$ rak foo --extensions=

# inspect files without extension or with the extension "foo"
$ rak foo --extensions=,foo

Predefined groups are #raku, #perl, #cro, #text, #c, #c++, #yaml, #ruby, #python, #html, #markdown, #js, #json, #jsonl, #csv, #config and #text.

The --list-known-extensions argument can be used to see which predefined groups of extensions are supported, and which extensions they cover.

--file=condition

If specified, indicates the Callable that should return True to have a file be included in the file selection process. The basename of the file will be passed as the only argument. Defaults to True, indicating that all files should be included.

If --/file is specified, then only directory paths will be accepted. This only makes sense if --find is also specified.

--file-separator-null

Flag. Indicate to separate filenames by null bytes rather than newlines if the --files-with-matches or --files-without-matches option are specified with a True value.

--files-from=filename

Indicate the path of the file to read filenames from instead of the expansion of paths from any positional arguments. "-" can be specified to read filenames from STDIN.

--files-with-matches

Flag. If specified, will only produce the filenames of the files in which the pattern was found. Defaults to False.

--files-without-matches

Flag. If specified, will only produce the filenames of the files in which the pattern was not found. Defaults to False.

--filesize=condition

If specified, indicates the Callable that should return True to include a file in the selection of files to be checked. The number of bytes of data in the file, will be passed as the only argument. See also --is-empty.

# show files that consist of at 30 bytes
$ rak --find --filesize='* >= 30'

--find

Flag. If specified, will not look at the contents of the selected paths, but instead consider the selected paths as lines in a virtual file. And as such will always only produce filenames.

--only-first[=N]

Indicate the overall number of matches to show. If specified without a value, will default to 1. Defaults to 1000 if a human is watching, otherwise defaults to returning all possible matches. Can be used to tweak search results, before letting it loose to get all possible results.

Special values that are allowed to produce all possible results are (aka 221E INFINITY), * and Inf.

--formula=[none]

Only applicable if --csv-per-line has been specified. If specified, indicates the action to be taken when a field starts with an equal sign (indicating a formula of some kind in many spreadsheets). The following values are recognized:

--frequencies

Flag. If specified, will produce a frequency table of the matches with the most frequent match first. Default is False. See also --unique. Usually used in conjunction with --matches-only and/or Callable patterns returning something other than True/False/Nil/Empty.

--gid=condition

If specified, indicates the Callable that should return True to include a file in the selection of files to be checked. The numeric gid of the file will be passed as the only argument. Can also be specified as a single numeric argument. See also --group.

# show files of which the numeric group id is greater than 20
$ rak --find --gid='* > 20'

# show files of which the numeric group id is 20
$ rak --find --gid=20

NOTE: support of this feature depends on Raku supporting that feature on the current operating system.

--group=condition

If specified, indicates the Callable that should return True to include a file in the selection of files to be checked. The name of the group associated with the gid of the file will be passed as the only argument.

Can also be specified as a list of comma separated names to (not) select on. To select all names except the listed named, prefix with a !.

See also --gid. Requires the P5getgrnam module to be installed.

# files of which the name associated with the user id starts with underscore
$ rak --find --group='*.starts-with("_")'

# show files of which the group is "staff"
$ rak --find --group=staff

# show files of which the group is NOT "staff"
$ rak --find --group='!staff'

NOTE: support of this feature depends on Raku supporting that feature on the current operating system.

--group-matches

Flag. Indicate whether matches of a file should be grouped together by mentioning the filename only once (instead of on every line). Defaults to True if a human is watching, else False.

If specified, indicates the Callable that should return True to include a file in the selection of files to be checked. The number of hard-links to the file on the filesystem, will be passed as the only argument.

--has-setgid

Flag. If specified, will only select files that do have the SETGID bit set in their attributes. Use negation --/has-setgid to only select files that do not have the SETGID bit set.

NOTE: support of this feature depends on Raku supporting that feature on the current operating system.

--has-setuid

Flag. If specified, will only select files that do have the SETUID bit set in their attributes. Use negation --/has-setuid to only select files that do not have the SETUID bit set.

NOTE: support of this feature depends on Raku supporting that feature on the current operating system.

--headers

Only applicable when --csv-per-line is also specified. It defaults to "auto". It can have the following values:

Boolean True, same as "auto"

Boolean False, assume comma separator and no header line, produce a list of column values for each line in the CSV file.

Automatically determine separator, first line is header with column names, produce a hash with values keyed to column names for each line in the CSV file.

Assume the first line is a header, but skip it. Produce a lust of column values for each line in the CSV file.

Same as "auto", but uppercase the column names found in the header line.

Same as "auto", but lowercase the column names found in the header line.

Specifies a list of column names to associate with columns, in order. Assumes no header line is available.

Indicates a list of Pairs with column name mapping to use instead of the column names found in the header line of the CSV file.

Any Raku code that produces one of the above values. Also supports a Map or Hash instead of a list of Pairs.

# Use uppercase column names
$ rak --csv-per-line --headers=uc '{.<FOO> if .<BAR> eq "foo"}' info.csv

# Use alternate column names in order of columns
$ rak --csv-per-line --headers='<a b>' '{.<a> if .<n> eq "foo"}' info.csv

# Use alternate column names using mapping
$ rak --csv-per-line --headers=':foo<a>, :bar<b>' '{.<a> if .<n> eq "foo"}' info.csv

--help[=area-of-interest]

Show argument documentation, possibly extended by giving the area of interest, which are:

If no area of interest is given, then the overview will be shown.

Any pattern specification will be used to search the help subjects, and only show the logical paragraphs with matches.

--highlight

Flag. Indicate whether the pattern should be highlighted in the line in which it was found. Defaults to True if a human is watching (aka STDOUT connected to a terminal), or --highlight-before or highlight-after are explicitely specified, or False otherwise.

--highlight--after[=string]

Indicate the string that should be used at the end of the pattern found in a line. Specifying implies --highlighting implicitely. If --highlight or --highlight-before are explicitely specified, will default to whatever is specified with --highlight-before, or to the ANSI code to end bold.

--highlight--before[=string]

Indicate the string that should be used at the end of the pattern found in a line. Specifying implies --highlighting implicitly. If highlight is explicitely specified, will default to the terminal code to start bold.

--human

Flag. Indicate that search results should be presented in a human readable manner. This means: filenames shown on a separate line, line numbers shown, and highlighting performed. Defaults to True if STDOUT is a TTY (aka, someone is actually watching the search results), otherwise defaults to False.

--ignorecase

Flag. If specified, indicates that any matching using a literal string or a regex, should be done case insensitively. Default is False.

--ignoremark

Flag. If specified, indicates that any matching using a literal string or a regex, should be done without consideration of any accents. Default is False.

--inode=condition

If specified, indicates the Callable that should return True to include a file in the selection of files to be checked. The inode number of the file on the filesystem, will be passed as the only argument.

NOTE: support of this feature depends on Raku supporting that feature on the current operating system.

--invert-match

Flag. If specified, will negate the result of any match if it has a logical meaning:

--is-empty

Flag. If specified, will only select files that do not contain any data. Use negation --/is-empty to only select files that do contain data. Special case of --filesize.

--is-executable

Flag. If specified, will only select files that can be executed by the current user. Use negation --/is-executable to only select files that are not executable by the current user.

NOTE: support of this feature depends on Raku supporting that feature on the current operating system.

--is-group-executable

Flag. If specified, will only select files that can be executed by members of the group of the owner. Use negation --/is-group-executable to only select files that are not executable by the members of the group of the owner.

NOTE: support of this feature depends on Raku supporting that feature on the current operating system.

--is-group-readable

Flag. If specified, will only select files that can be read by members of the group of the owner. Use negation --/is-group-readable to only select files that are not readable by the members of the group of the owner.

NOTE: support of this feature depends on Raku supporting that feature on the current operating system.

--is-group-writable

Flag. If specified, will only select files that can be written to by members of the group of the owner. Use negation --/is-group-writable to only select files that are not writable by the members of the group of the owner.

NOTE: support of this feature depends on Raku supporting that feature on the current operating system.

--is-owned-by-group

Flag. If specified, will only select files that are owned by the group of the current user. Use negation --/is-owned-by-group to only select files that are not owned by the group of the current user.

NOTE: support of this feature depends on Raku supporting that feature on the current operating system.

--is-owned-by-user

Flag. If specified, will only select files that are owned by current user. Use negation --/is-owned-by-user to only select files that are not owned by the current user.

NOTE: support of this feature depends on Raku supporting that feature on the current operating system.

--is-owner-executable

Flag. If specified, will only select files that can be executed by the owner. Use negation --/is-owner-executable to only select files that are not executable by the owner.

NOTE: support of this feature depends on Raku supporting that feature on the current operating system.

--is-owner-readable

Flag. If specified, will only select files that can be read by the owner. Use negation --/is-owner-readable to only select files that are not readable by the owner.

NOTE: support of this feature depends on Raku supporting that feature on the current operating system.

--is-owner-writable

Flag. If specified, will only select files that can be written to by the owner. Use negation --/is-owner-writable to only select files that are not writable by the owner.

NOTE: support of this feature depends on Raku supporting that feature on the current operating system.

--is-readable

Flag. If specified, will only select files that can be read by the current user. Use negation --/is-readable to only select files that are not readable by the current user.

--is-sticky

Flag. If specified, will only select files that do have the STICKY bit set in their attributes. Use negation --/is-sticky to only select files that do not have the STICKY bit set.

NOTE: support of this feature depends on Raku supporting that feature on the current operating system.

Flag. If specified, will only select files that are symbolic links. Use negation --/is-symbolic-link to only select files that are not symbolic links.

NOTE: support of this feature depends on Raku supporting that feature on the current operating system.

--is-text

Flag. If specified, will only select files that appear to contain text (rather than binary data). Use negation --/is-text to only select files with binary data.

Note: support for searching for binary data is not yet implemented, so --/is-text can only be used in conjunction with --find.

--is-world-executable

Flag. If specified, will only select files that can be executed by anybody. Use negation --/is-group-executable to only select files that are not executable by anybody.

NOTE: support of this feature depends on Raku supporting that feature on the current operating system.

--is-world-readable

Flag. If specified, will only select files that can be read by anybody. Use negation --/is-world-readable to only select files that are not readable by anybody.

NOTE: support of this feature depends on Raku supporting that feature on the current operating system.

--is-world-writable

Flag. If specified, will only select files that can be written to by anybody. Use negation --/is-world-writable to only select files that can not be written to by anybody.

NOTE: support of this feature depends on Raku supporting that feature on the current operating system.

--is-writable

Flag. If specified, will only select files that can be written to by the current user. Use negation --/is-writable to only select files that can not be written to by the current user.

--json-per-elem

Flag. Only makes sense if the pattern is a Callable. If specified, indicates that each selected file will be interpreted as JSON, and if valid, will then produce all elements of the outermost data structure to the pattern for introspection. If the data structure is a hash, then key/value Pairs will be produced.

If the Callable returns True, the stringification of the element will be produced. If the returned value is a string, that string will be produced. For example when searching the list of modules in the zef ecosystem (which consists of an array of hashes):

# Show all defined "auth" values of top elemens in JSON file
$ rak '{ .<auth> // False }' META.json --json-per-elem

--json-per-file

Flag. Only makes sense if the pattern is a Callable. If specified, indicates that each selected file will be interpreted as JSON, and if valid, will then be given to the pattern for introspection. If the Callable returns True, the filename will be produced. If anything else is returned, then the stringification of that object will be produced. For example:

# show the "auth" value from all JSON files
$ rak '*<auth> // False' --json-per-file

--json-per-line

Flag. Only makes sense if the pattern is a Callable. If specified, indicates that each line from the selected files will be interpreted as JSON, and if valid, will then be given to the pattern for introspection. If the Callable returns True, the filename and line number will be produced. If the returned value is anything else, then the stringification of that object will be be produced. For example:

# show the "auth" value from the JSON blob on each line
$ rak '{ $_ with .<auth> }' --json-per-line

--keep-meta

Flag. Only applicable if --csv-per-line has been specified. If specified, indicates that meta-information will be kept for each field, by presenting each field as a CSV::Field|https://github.com/Tux/CSV/blob/master/doc/Text-CSV.md#csvfield object rather than as a string. The most important methods that can be called on a CSV::Field object are:

--list-custom-options

Flag. If specified as the only option, will list all additional options previously saved with --save.

# show all of the custom options
$ rak --list-custom-options
fs: --'follow-symlinks'
im: --ignorecase --ignoremark

--list-expanded-options

Flag. If specified, will show all actual options being activated after having been recursively expanded, and then exit. Intended as a debugging aid if you have many custom options defined.

# show how custom option "--im" expands
$ rak --im --list-expanded-options
--ignorecase --ignoremark

--list-known-extensions

Flag. If specified, will show all known extension groups and the extensions they represent. Intended as an informational aid.

# show the filename extensions that "rak" knows about
$ rak --list-known-extensions
       #c: c h hdl
     #c++: cpp cxx hpp hxx
  #config: ini
     #cro: (none) crotmp
     #csv: (none) csv psv tsv
    #html: htm html css
      #js: js ts tsx
    #json: json
   #jsonl: jsonl
#markdown: md markdown
    #perl: (none) pl pm t
  #python: py ipynb
    #raku: (none) raku rakumod rakutest rakudoc nqp t pm6 pl6 pod6 t6
    #ruby: rb
    #text: (none) txt
    #yaml: yaml yml

--matches-only

Flag. Indicate whether only the matched pattern should be produced, rather than the line in which the pattern was found. Defaults to False. Frequently used in conjunction with --per-file. Will show separated by space if multiple matches are found on the same line.

--max-matches-per-file[=N]

Indicate the maximum number of matches that should be produced per file. If specified as a flag, will assume 1 for its value. By default, will produce all possible matches in a file.

---meta-modified=condition

If specified, indicates the Callable that should return True to include a file in the selection of files to be checked. The modification time of meta information of the file (number of seconds since epoch, as a Num value) will be passed as the only argument.

See "CHECKING TIMES ON FILES" for more information about features that can be used inside the Callable.

NOTE: support of this feature depends on Raku supporting that feature on the current operating system.

--mode=condition

If specified, indicates the Callable that should return True to include a file in the selection of files to be checked. The full numeric mode value of the file on the filesystem, will be passed as the only argument.

# list files with sticky bit set
$ rak --find --mode='{ $_ +& 0o1000 }'

NOTE: support of this feature depends on Raku supporting that feature on the current operating system.

--modified=condition

If specified, indicates the Callable that should return True to include a file in the selection of files to be checked. The modification time of the file (number of seconds since epoch, as a Num value) will be passed as the only argument.

See "CHECKING TIMES ON FILES" for more information about features that can be used inside the Callable.

--modify-files

Flag. Only makes sense if the specified pattern is a Callable. Indicates whether the output of the pattern should be applied to the file in which it was found. Defaults to False.

The Callable will be called for each file (in sorted order) and each line of the file, giving the line (including its line ending). The $*N dynamic variable is available inside the Callable and is initialized to 0 (in case modifications require keeping numeric state between calls). It is then up to the Callable to return:

False

Remove this line from the file. NOTE: this means the exact False value.

True

Keep this line unchanged the file. NOTE: this means the exact True value.

Nil

Keep this line unchanged the file. NOTE: this means the exact Nil value.

Empty

Keep this line unchanged the file. NOTE: this means the exact Empty value. This is typically returned as the result of a failed condition. For example, only change the string "foo" into "bar" if the line starts with "#":

# replace "foo" by "bar" in all comment lines
$ rak '{ .subst("foo","bar") if .starts-with("#") }' --modify-files

any other value

Inserts this value in the file instead of the given line. The value can either be a string, or a list of strings (which would add lines to the file).

--module=Foo

Indicate the Raku module that should be loaded. Only makes sense if the pattern is a Callable.

--output-dir=directory

Specify the name of the directory to store the results in. For each group, a separate file will be created. Usually used in conjunction with --classify or --categorize, but can also be used for normal search results. In that case, the basename of a file with results, will be taken as the name of the file to create in that output directory. The directory must not exist beforehand.

--output-file=filename

Indicate the path of the file in which the result of the search should be placed. Defaults to STDOUT.

--pager=name

Indicate the name (and arguments) of a pager program to be used to page through the generated output. Defaults to the RAK_PAGER environment variable. If that isn't specified either, then no pager program will be run.

# use the "more" pager to page the output
$ RAK_PAGER='more -r' rak foo

# use the "less" pager to page the output
$ rak foo --pager='less -r'

--paragraph-context

Flag. Indicate all lines that are part of the same paragraph around any line that matches. Defaults to False. Paragraph boundaries are:

--passthru

Flag. Indicate whether all lines from source should be shown always. Highlighting will still be performed, if so (implicitely) specified.

# watch a log file, and highlight a IP address 123.45.67.89
$ tail -f ~/access.log | rak --passthru 123.45.67.89

--passthru-context

Flag. Indicate whether all lines from source should be produced if at least one line matches. Highlighting will still be performed, if so (implicitely) specified.

--paths=path1,path2

Indicates the path specification to be used instead of from any positional arguments. Multiple path specifications should be separated by comma's.

--paths-from=filename

Indicate the path of the file to read path specifications from instead of from any positional arguments. "-" can be specified to read path specifications from STDIN.

--pattern=foo

Alternative way to specify the pattern to search for. If (implicitly) specified, will assume the first positional parameter specified is actually a path specification, rather than a pattern. This allows the pattern to be saved with --save, and thus freeze a specific pattern as part of a custom option.

--patterns-from=file

Alternative way to specify one or more patterns to search for. Reads the indicated file and interprets each line as a pattern according to the rules (implicitly) set with the --type argument. If the file specification is "-", then the patterns will be read from STDIN.

--per-file[=code]

Indicate whether matching should be done per file, rather than per line. If specified as a flag, will slurp a file with the indicated --encoding and present that to the matcher. Optionally takes a Callable specification: this will be given an IO::Path object of the file: whatever it produces will be presented to the matcher. Usually used in conjunction with --matches-only and/or count-only.

# look for foo in only the first 10 lines of each file
$ rak foo --per-file='*.lines(:!chomp).head(10).join'

--per-line[=code]

Indicate whether matching should be done per line. If specified as a flag, will read lines with the indicated --encoding and present each line to the matcher (which is actually the default if no action was specified).i

Optionally takes a Callable specification: this will be given an IO::Path object of the file: that is then expected to produce lines that will be presented to the matcher.

# look for foo in only the last 10 lines of each file
$ rak foo --per-line='*.lines.tail(10)'

--proximate=[N]

Indicates whether matched lines should be grouped together that are within N lines of each other. This is useful for visually picking out matches that appear close to other matches. If specified as a flag, indicates a proximation of 1. Defaults to <0> otherwise (indicating no proximation check should be performed).

--quietly

Flag. Only makes sense if the pattern is a Callable. If specified, will catch all warnings that are emitted when executing the pattern's Callable. Defaults to False.

--quote=["]

Only applicable if --csv-per-line has been specified. Indicates the character that should be used for quoting fields. Defaults to double quote.

--rak

Flag. Intended for debugging purposes only. When specified, will show the named arguments sent to the rak plumbing subroutine just before it isi being called.

--recurse-unmatched-dir

Flag. Indicate whether directories that didn't match the --dir specification, should be recursed into anyway. Will not produce files from such directories, but may recurse further if directories are encountered. Defaults to False.

--recurse-symlinked-dir

Flag. Indicate whether directories that are actually symbolic links, should be recursed into. Defaults to False.

NOTE: support of this feature depends on Raku supporting that feature on the current operating system.

--rename-files

Flag. Only makes sense if the specified pattern is a Callable. Feeds all selected files, sorted by absolute path, as IO::Path objects to the pattern, and uses the result (if different from the original) as the new name of the file.

The --dryrun argument can be used to run through the whole process except doing actually any renaming.

The --verbose argument can be used to get more verbose feedback on the operation.

The Callable will be called for each line, giving the file as an IO::Path object. The $*N dynamic variable is available inside the Callable and is initialized to 0. It is then up to the Callable to return:

False

Don't change the name of the file NOTE: this means the exact False value.

True

Don't change the name of the file. NOTE: this means the exact True value.

Nil

Don't change the name of the file. NOTE: this means the exact Nil value.

Empty

Don't change the name of the file. NOTE: this means the exact Empty value. This is typically returned as the result of a failed condition.

any other value

Use this value as the new name of the file. It can either be a string or an IO::Path object. Only when the returned value is different from the given value, will a rename actually be attempted. To make this easier on the user, any Str returned, will be automatically converted to an IO::Path object before being compared using eqv.

# change the extension of all .t files to .rakutest
$ rak '*.subst(/ \.t $/,".rakutest")' --rename-files

# Rename files with 3 digits word bounded with an interval of 10
$ rak '*.subst(/ << \d ** 3 >> /, { ($*N += 10).fmt("%03d") })' --rename-files

Note that files that are under git revision control will be renamed using git mv: if that fails for any reason, a normal rename will be performed.

--repository=dir

Indicate the directory that should be searched for Raku module loading. Only makes sense if the pattern is executable code.

--save=shortcut-name

Save all options with the given name in the configuration file (~/.rak-config.json), and exit with a message that these options have been saved with the given name.

This feature can used to both create shortcuts for specific (long) options, or just as a convenient way to combine often used options, or both.

# save options as "--im"
$ rak --ignorecase --ignoremark --save=im
Saved option '--im' as: --ignorecase --ignoremark

# can use shortcut to --ignorecase --ignoremark
$ rak foo --im

# save options as "--rsd"
$ rak --recurse-symlinked-dir --save=rsd
Saved option '--rsd' as: --recurse-symlinked-dir

# save as "--B" with a default of '---'
$ rak --break='[---]' --save=B
Saved option '--B' as: --break='[---]'

# save as "--P" requiring a value
$ rak --pattern=! --save=P
Saved option '--P' as: --pattern='!'

# remove shortcut "--foo"
$ rak --save=foo
Removed configuration for 'foo'

Any options can be accessed as if it is a standard option. Please note that no validity checking on the options is being performed at the moment of saving, as validity may depend on other options having been specified.

One option can be marked as requiring a value to be specified (with "!") or have a default value (with "[default-value]").

To remove a saved set of options, use --save=foo as the only option to remove the "foo" set of options.

--sep=,

Only applicable if --csv-per-line has been specified. Indicates the character to indicate the field separator. Defaults to the comma.

--show-blame

Flag. Indicate whether to show git blame information for matching lines if possible, instead of just the line. Defaults to False.

Requires that the Git::Blame::File module is installed.

--show-item-number

Flag. Indicate whether item numbers should be shown. Defaults to True.

--show-filename

Flag. Indicate whether filenames should be shown. Defaults to True.

--shell=invocation

If specified, indicates the command(s) to be executed in a shell. Any $_ in the invocation string will be replaced by the file being checked. The file will be included if the shell command(s) run to a successful conclusion.

--silently[=out,err]

Flag and option. Only applicable if the pattern is a Callable. Indicates whether any output from the Callable pattern should be caught. Defaults to False. If specified as a flag, will catch both STDOUT as well as STDERR output from the pattern's execution. When specified as an option, will accept:

--smartcase

Flag. An intelligent version of --ignorecase. If the pattern does not contain any uppercase letters, it will act as if --ignorecase was specified. Otherwise it is ignored.

--smartmark

Flag. An intelligent version of --ignoremark. If the pattern does not contain any accented letters, it will act as if --ignoremark was specified. Otherwise it is ignored.

--sourcery

Flag. Mainly intended for Raku Programming Language core developers. If specified, indicates that the pattern should be interpreted as code specifying a simple call to a subroutine, or a simple call to a method, optionally with arguments. The search result will then contain the source locations of subroutine / method that is expected to be able to handle that call.

Compatible with the --edit, --vimgrep and the implicit per-line option.

# edit the location(s) of the "say" sub handling a single string
$ rak --sourcery 'say "foo"' --edit

Requires that the sourcery module is installed.

--stats

Flag. Also show statistics about the search operation after having shown the full search result.

--stats-only

Flag. Only show statistics about the search operation. See also --count-only.

--strict

Flag. Only applicable if --csv-per-line has been specified. If specified, then each line in the CSV file must have the same number of fields. Default is to allow different numbers of fields.

--summary-if-larger-than=N

Indicate the maximum size a line may have before it will be summarized. Defaults to 160 if STDOUT is a TTY (aka, someone is actually watching the search results), otherwise defaults to Inf effectively (indicating no summarization will ever occur).

--type=string

The --type argument indicates how any pattern, as specified on the commmand line, or from previously saved options, should be interpreted. If not specified specified, will assume auto.

The following strings can be specified:

auto

If --type=auto is (implicitely) specified, will look for cues in a specified pattern to understand what functionality is requested. See the pattern for more information.

regex

If --type=regex is specified, then a pattern will be interpreted as a regex, as if it was surrounded by slashes.

code

If --type=code is specified, then a pattern will be interpreted as Raku source code, as if it was surrounded by curly braces.

json path

If --type=json-path is specified, then a pattern will be interpreted as a JSON path. Only makes sense when used together with --json-per-file, --json-per-line or --json-per-elem. Requires that the JSON::Path module is installed.

contains

If --type=contains is specified, then a pattern will be interpreted as a literal string, while honouring any --smartcase, --smartmark, --ignorecase and --ignoremark specifications.

words

If --type=words is specified, then a pattern will be interpreted as a literal string that should be bounded by word boundares at both ends, while honouring any --smartcase, --smartmark, --ignorecase and --ignoremark specifications.

starts-with

If --type=starts-with is specified, then a pattern will be interpreted as a literal string that should occur at the start of a line, while honouring any --smartcase, --smartmark, --ignorecase and --ignoremark specifications.

ends-with

If --type=ends-with is specified, then a pattern will be interpreted as a literal string that should occur at the end of a line, while honouring any --smartcase, --smartmark, --ignorecase and --ignoremark specifications.

equal

If --type=equal is specified, then a pattern will be interpreted as a literal string that should be equal to the line, while honouring any --smartcase, --smartmark, --ignorecase and --ignoremark specifications.

--trim

Flag. Indicate whether lines that have the pattern, should have any whitespace at the start and/or end of the line removed. Defaults to True if no context for lines was specified, else defaults to False.

--uid=condition

If specified, indicates the Callable that should return True to include a file in the selection of files to be checked. The numeric uid of the file will be passed as the only argument. Can also be specified as a single numeric argument. See also --user.

# select files of which the numeric user id is greater than 500
$ rak --find --uid='* > 500'

# select files of which the numeric user id is 501
$ rak --find --uid=501

NOTE: support of this feature depends on Raku supporting that feature on the current operating system.

--under-version-control[=git]

Indicate whether to only select files that are under some form of version control. If specified as a flag, will assume files that are under git version control. Can also specify the name of the version control system as the value: currently only git is supported.

--unicode

Flag. If specified, will search the unicode database for defined codepoints by name. Default is False.

--unique

Flag. If specified, will only produce unique lines of output. Default is False. See also --frequencies.

--user=condition

If specified, indicates the Callable that should return True to include a file in the selection of files to be checked. The user name associated with the uid of the file will be passed as the only argument.

Can also be specified as a list of comma separated names to (not) select on. To select all names except the listed named, prefix with a !.

See also --uid. Requires the P5getpwnam module to be installed.

# files of which the name associated with the user id starts with underscore
$ rak --find --user='*.starts-with("_")'

# select files of which the owner is liz or wendy
$ rak --find --user=liz,wendy

# select files of which the owner is NOT liz or wendy
$ rak --find --user='!liz,wendy'

NOTE: support of this feature depends on Raku supporting that feature on the current operating system.

--version

Flag. If the only argument, shows the name and version of the script, and the system it is running on. Additionally specify --verbose to see more information.

--vimgrep

Flag. If specified, will output search results in the format "filename:linenumber:column:line". This allows integration with the :grep action in vim-like editors.

CHECKING TIMES ON FILES

The --accessed, --created, --modified and --meta-modified options expect Callable to perform the check to include a file in the search process. It is passed the epoch (number of seconds since 1 January 1970 UTC) value of the file being checked for the indicated option, and it should return True to include that file in any search.

To facilitate checks, some extra features are activated for these Callables, allowing you to more easily craft your conditions.

Automatic conversion to epoch

In Raku, the .accessed, .created, .changed and .modified methods on the IO::Path object return Instant objects, which are atomic time rather than epoch. Within these special Callables, these values are automatically converted to epoch values, to ease comparisons.

Specifying some time ago

Within these special Callables, one can also indicate an epoch value in the past by using the .ago method in a specially formatted string. This string is formatted similarly to time specifications of the Unix find command: one of more digits followed by "s" for seconds, "m" for minutes, "h" for hours, "d" for days and "w" for weeks. "+" and "-" may also be used, but do not have any special meaning other than negating the value they apply to.

On method naming

For rak it was decided to name the option for checking the meta information of a file as --meta-modified. In Raku, the associated method on the IO::Path object is (probably for historical reasons) called .changed. To facilitate the creation of the Callables for these options, one can use both .meta-modified as well as .changed as methods.

Examples

# select all files that were modified later than an hour ago
$ rak --find --modified='* > "1h".ago'

# select all files that were created before 2.5 hours ago
$ rak --find --created='* < "2h30m".ago'

# select all files that were modified after "Changes" was created
$ rak --find --modified='* > "Changes".IO.created'

AUTHOR

Elizabeth Mattijsen [email protected]

Source can be located at: https://github.com/lizmat/App-Rak . Comments and Pull Requests are welcome.

If you like this module, or what I’m doing more generally, committing to a small sponsorship would mean a great deal to me!

COPYRIGHT AND LICENSE

Copyright 2022 Elizabeth Mattijsen

This library is free software; you can redistribute it and/or modify it under the Artistic License 2.0.