Term::Choose(3pm)

User Contributed Perl Documentation

Term::Choose(3pm)

NAME¶

Term::Choose - Choose items from a list interactively.

VERSION¶

Version 1.713

SYNOPSIS¶

Functional interface:

    use Term::Choose qw( choose );
    my $array_ref = [ qw( one two three four five ) ];
    my $choice = choose( $array_ref );                            # single choice
    print "$choice\n";
    my @choices = choose( [ 1 .. 100 ], { alignment => 1 } );     # multiple choice
    print "@choices\n";
    choose( [ 'Press ENTER to continue' ], { prompt => '' } );    # no choice

Object-oriented interface:

    use Term::Choose;
    my $array_ref = [ qw( one two three four five ) ];
    my $new = Term::Choose->new();
    my $choice = $new->choose( $array_ref );                       # single choice
    print "$choice\n";
    my @choices = $new->choose( [ 1 .. 100 ] );                    # multiple choice
    print "@choices\n";
    my $stopp = Term::Choose->new( { prompt => '' } );
    $stopp->choose( [ 'Press ENTER to continue' ] );               # no choice

DESCRIPTION¶

Choose interactively from a list of items.

"Term::Choose" provides a functional interface ("SUBROUTINES") and an object-oriented interface ("METHODS").

EXPORT¶

Nothing by default.

    use Term::Choose qw( choose );

METHODS¶

new¶

    $new = Term::Choose->new( [ \%options] );

This constructor returns a new "Term::Choose" object.

To set the different options it can be passed a reference to a hash as an optional argument.

For detailed information about the options see "OPTIONS".

choose¶

The method "choose" allows the user to choose from a list.

The first argument is an array reference which holds the list of the available choices.

As a second and optional argument it can be passed a reference to a hash where the keys are the option names and the values the option values.

Options set with "choose" overwrite options set with "new". Before leaving "choose" restores the overwritten options.

    $choice = $new->choose( $array_ref [, \%options] );
    @choices= $new->choose( $array_ref [, \%options] );
              $new->choose( $array_ref [, \%options] );

When in the documentation is mentioned "array" or "list" or "elements" or "items" (of the array/list) than these refer to this array passed as a reference as the first argument.

For more information how to use "choose" and its return values see "USAGE AND RETURN VALUES".

SUBROUTINES¶

choose¶

The function "choose" allows the user to choose from a list. It takes the same arguments as the method "choose".

    $choice = choose( $array_ref [, \%options] );
    @choices= choose( $array_ref [, \%options] );
              choose( $array_ref [, \%options] );

See the "OPTIONS" section for more details about the different options and how to set them.

See also the following section "USAGE AND RETURN VALUES".

USAGE AND RETURN VALUES¶

If "choose" is called in a scalar context, the user can choose an item by using the "Keys to move around" and confirming with "Return".
"choose" then returns the chosen item.
If "choose" is called in an list context, the user can also mark an item with the "SpaceBar".
"choose" then returns - when "Return" is pressed - the list of marked items (including the highlighted item if the option include_highlighted is set to 1).

In list context "Ctrl-SpaceBar" (or "Ctrl-@") inverts the choices: marked items are unmarked and unmarked items are marked.
If "choose" is called in an void context, the user can move around but mark nothing; the output shown by "choose" can be closed with "Return".
Called in void context "choose" returns nothing.

If the first argument refers to an empty array, "choose" returns nothing.

If the items of the list don't fit on the screen, the user can scroll to the next (previous) page(s).

If the window size is changed, then as soon as the user enters a keystroke "choose" rewrites the screen.

"choose" returns "undef" or an empty list in list context if the "q" key (or "Ctrl-Q") is pressed.

If the mouse mode is enabled, an item can be chosen with the left mouse key, in list context the right mouse key can be used instead the "SpaceBar" key.

Keys to move around¶

the "Arrow" keys (or the "h,j,k,l" keys) to move up and down or to move to the right and to the left,
the "Tab" key (or "Ctrl-I") to move forward, the "BackSpace" key (or "Ctrl-H" or "Shift-Tab") to move backward,
the "PageUp" key (or "Ctrl-B") to go back one page, the "PageDown" key (or "Ctrl-F") to go forward one page,
the "Insert" key to go back 10 pages, the "Delete" key to go forward 10 pages,
the "Home" key (or "Ctrl-A") to jump to the beginning of the list, the "End" key (or "Ctrl-E") to jump to the end of the list.

Modifications for the output¶

For the output on the screen the array elements are modified.

All the modifications are made on a copy of the original array so "choose" returns the chosen elements as they were passed to the function without modifications.

Modifications:

If an element is not defined the value from the option undef is assigned to the element.
If an element holds an empty string the value from the option empty is assigned to the element.
Tab characters in elements are replaces with a space.
```
    $element =~ s/\t/ /g;
    
```
Vertical spaces in elements are squashed to two spaces.
```
    $element =~ s/\v+/\ \ /g;
    
```
Code points from the ranges of control, surrogate and noncharacter are removed.
```
    $element =~ s/[\p{Cc}\p{Noncharacter_Code_Point}\p{Cs}]//g;
    
```
If the length of an element is greater than the width of the screen the element is cut and at the end of the string are added three dots.

OPTIONS¶

Options which expect a number as their value expect integers.

alignment

0 - elements ordered in columns are aligned to the left (default)

1 - elements ordered in columns are aligned to the right

2 - elements ordered in columns are centered

beep

0 - off (default)

1 - on

clear_screen

0 - off (default)

1 - clears the screen before printing the choices

codepage_mapping

This option has only meaning if the operating system is MSWin32.

If the OS is MSWin32, Win32::Console::ANSI is used. By default "Win32::Console::ANSI" converts the characters from Windows code page to DOS code page (the so-called ANSI to OEM conversion). This conversation is disabled by default in "Term::Choose" but one can enable it by setting this option.

Setting this option to 1 enables the codepage mapping offered by Win32::Console::ANSI.

0 - disable automatic codepage mapping (default)

1 - keep automatic codepage mapping

color

Enable the support for color and text formatting escape sequences.

0 - off (default)

1 - Enables the support for color and text formatting escape sequences except for the current selected element.

2 - Enables the support for color and text formatting escape sequences including for the current selected element (shown in inverted colors).

default

With the option default it can be selected an element, which will be highlighted as the default instead of the first element.

default expects a zero indexed value, so e.g. to highlight the third element the value would be 2.

If the passed value is greater than the index of the last array element the first element is highlighted.

Allowed values: 0 or greater

(default: undefined)

empty

Sets the string displayed on the screen instead an empty string.

(default: "<empty>")

footer

Add a string in the bottom line.

(default: undefined)

hide_cursor

0 - keep the terminals highlighting of the cursor position

1 - hide the terminals highlighting of the cursor position (default)

info

Expects as its value a string. The info text is printed above the prompt string.

(default: not set)

index

0 - off (default)

1 - return the index of the chosen element instead of the chosen element respective the indices of the chosen elements instead of the chosen elements.

keep

keep prevents that all the terminal rows are used by the prompt lines.

Setting keep ensures that at least keep terminal rows are available for printing list rows.

If the terminal height is less than keep keep is set to the terminal height.

Allowed values: 1 or greater

(default: 5)

layout

From broad to narrow: 0 > 1 > 2 > 3

0 - layout off

 .----------------------.   .----------------------.   .----------------------.   .----------------------.
 | .. .. .. .. .. .. .. |   | .. .. .. .. .. .. .. |   | .. .. .. .. .. .. .. |   | .. .. .. .. .. .. .. |
 |                      |   | .. .. .. .. .. .. .. |   | .. .. .. .. .. .. .. |   | .. .. .. .. .. .. .. |
 |                      |   |                      |   | .. .. .. .. ..       |   | .. .. .. .. .. .. .. |
 |                      |   |                      |   |                      |   | .. .. .. .. .. .. .. |
 |                      |   |                      |   |                      |   | .. .. .. .. .. .. .. |
 |                      |   |                      |   |                      |   | .. .. .. .. .. .. .. |
 '----------------------'   '----------------------'   '----------------------'   '----------------------'

1 - layout "H" (default)

 .----------------------.   .----------------------.   .----------------------.   .----------------------.
 | .. .. .. .. .. .. .. |   | .. .. .. .. ..       |   | .. .. .. .. .. ..    |   | .. .. .. .. .. .. .. |
 |                      |   | .. .. .. .. ..       |   | .. .. .. .. .. ..    |   | .. .. .. .. .. .. .. |
 |                      |   | .. ..                |   | .. .. .. .. .. ..    |   | .. .. .. .. .. .. .. |
 |                      |   |                      |   | .. .. .. .. .. ..    |   | .. .. .. .. .. .. .. |
 |                      |   |                      |   | .. .. ..             |   | .. .. .. .. .. .. .. |
 |                      |   |                      |   |                      |   | .. .. .. .. .. .. .. |
 '----------------------'   '----------------------'   '----------------------'   '----------------------'

2 - layout "V"

 .----------------------.   .----------------------.   .----------------------.   .----------------------.
 | .. ..                |   | .. .. ..             |   | .. .. .. ..          |   | .. .. .. .. .. .. .. |
 | .. ..                |   | .. .. ..             |   | .. .. .. ..          |   | .. .. .. .. .. .. .. |
 | ..                   |   | .. .. ..             |   | .. .. .. ..          |   | .. .. .. .. .. .. .. |
 |                      |   | .. ..                |   | .. .. ..             |   | .. .. .. .. .. .. .. |
 |                      |   |                      |   | .. .. ..             |   | .. .. .. .. .. .. .. |
 |                      |   |                      |   |                      |   | .. .. .. .. .. .. .. |
 '----------------------'   '----------------------'   '----------------------'   '----------------------'

3 - all in a single column

 .----------------------.   .----------------------.   .----------------------.   .----------------------.
 | ..                   |   | ..                   |   | ..                   |   | ..                   |
 | ..                   |   | ..                   |   | ..                   |   | ..                   |
 | ..                   |   | ..                   |   | ..                   |   | ..                   |
 |                      |   | ..                   |   | ..                   |   | ..                   |
 |                      |   |                      |   | ..                   |   | ..                   |
 |                      |   |                      |   |                      |   | ..                   |
 '----------------------'   '----------------------'   '----------------------'   '----------------------'

If all elements have the same length, the length can be passed with this option. "choose" then doesn't calculate the length of the longest element itself but uses the passed value. length refers here to the number of print columns the element will use on the terminal.

If ll is set, "choose" returns always the index(es) of the chosen item(s) regardless of how index is set.

Undefined list elements are not allowed.

The replacements described in "Modifications for the output" are not applied. If elements contain unsupported characters the output might break.

If ll is set to a value less than the length of the elements, the output could break.

If ll is set and the window size has changed, choose returns immediately "-1".

Allowed values: 1 or greater

(default: undefined)

max_height

If defined sets the maximal number of rows used for printing list items.

If the available height is less than max_height then max_height is set to the available height.

Height in this context means print rows.

max_height overwrites keep if max_height is set to a value less than keep.

Allowed values: 1 or greater

(default: undefined)

max_width

If defined, sets the maximal output width to max_width if the terminal width is greater than max_width.

To prevent the "auto-format" to use a width less than max_width set layout to 0.

Width refers here to the number of print columns.

Allowed values: 1 or greater

(default: undefined)

mouse

0 - off (default)

1 - on. Enables the Any-Event-Mouse-Mode (1003) and the Extended-SGR-Mouse-Mode (1006).

If the option mouse is enabled layers for "STDIN" are changed. Then before leaving "choose" as a cleanup "STDIN" is marked as "UTF-8" with ":encoding(UTF-8)". This doesn't apply if the OS is MSWin32.

If the OS is MSWin32 the mouse is enabled with the help of Win32::Console.

order

If the output has more than one row and more than one column:

0 - elements are ordered horizontally

1 - elements are ordered vertically (default)

Default may change in a future release.

pad

Sets the number of whitespaces between columns. (default: 2)

Allowed values: 0 or greater

page

0 - off

1 - print the page number on the bottom of the screen if there is more then one page. (default)

prompt

If prompt is undefined a default prompt-string will be shown.

If the prompt value is an empty string ("") no prompt-line will be shown.

default in list and scalar context: "Your choice:"

default in void context: "Close with ENTER"

tabs_info

If info lines are folded, the option tabs_info allows one to insert spaces at beginning of the folded lines.

The option tabs_info expects a reference to an array with one or two elements:

- the first element (initial tab) sets the number of spaces inserted at beginning of paragraphs

- a second element (subsequent tab) sets the number of spaces inserted at the beginning of all broken lines apart from the beginning of paragraphs

Allowed values: 0 or greater. Elements beyond the second are ignored.

(default: undefined)

tabs_prompt

If prompt lines are folded, the option tabs_prompt allows one to insert spaces at beginning of the folded lines.

The option tabs_prompt expects a reference to an array with one or two elements:

- the first element (initial tab) sets the number of spaces inserted at beginning of paragraphs

- a second element (subsequent tab) sets the number of spaces inserted at the beginning of all broken lines apart from the beginning of paragraphs

Allowed values: 0 or greater. Elements beyond the second are ignored.

(default: undefined)

undef

Sets the string displayed on the screen instead an undefined element.

default: "<undef>"

Options List Context¶

include_highlighted

In list context when "Return" is pressed

0 - "choose" returns the items marked with the "SpaceBar". (default)

1 - "choose" returns the items marked with the "SpaceBar" plus the highlighted item.

2 - "choose" returns the items marked with the "SpaceBar". If no items are marked with the "SpaceBar", the highlighted item is returned.

mark

mark expects as its value a reference to an array. The elements of the array are list indexes. "choose" preselects the list-elements correlating to these indexes.

Elements greater than the last index of the list are ignored.

This option has only meaning in list context.

(default: undefined)

meta_items

meta_items expects as its value a reference to an array. The elements of the array are list indexes. These elements can not be marked with the "SpaceBar" or with the right mouse key but if one of these elements is the highlighted item it is added to the chosen items when "Return" is pressed.

Elements greater than the last index of the list are ignored.

This option has only meaning in list context.

(default: undefined)

no_spacebar

no_spacebar expects as its value a reference to an array. The elements of the array are indexes of the list which should not be markable with the "SpaceBar" or with the right mouse key.

If an element is preselected with the option mark and also marked as not selectable with the option no_spacebar, the user can not remove the preselection of this element.

no_spacebar elements greater than the last index of the list are ignored.

This option has only meaning in list context.

(default: undefined)

ERROR HANDLING¶

croak¶

"new|choose" dies if passed invalid arguments.

carp¶

If pressing a key results in an undefined value "choose" warns with "EOT: $!" and returns undef or an empty list in list context.

REQUIREMENTS¶

Perl version¶

Requires Perl version 5.8.3 or greater.

Optional modules¶

Term::ReadKey

If Term::ReadKey is available it is used "ReadKey" to read the user input and "GetTerminalSize" to get the terminal size. Without "Term::ReadKey" "getc" is used to read the input and "stty size" to get the terminal size.

If the OS is MSWin32 it is used Win32::Console to read the user input and to get the terminal size.

Decoded strings¶

"choose" expects decoded strings as array elements.

Encoding layer for STDOUT¶

For a correct output it is required an appropriate encoding layer for STDOUT matching the terminal's character set.

Monospaced font¶

It is required a terminal that uses a monospaced font which supports the printed characters.

Ambiguous width characters¶

By default ambiguous width characters are treated as half width. If the environment variable "TC_AMBIGUOUS_WIDE" is set to a true value, ambiguous width characters are treated as full width.

Escape sequences¶

By default "Term::Choose" uses "tput" to get the appropriate escape sequences. Setting the environment variable "TC_ANSI_ESCAPES" to a true value allows one to use ANSI escape sequences directly without calling "tput".

    BEGIN {
        $ENV{TC_ANSI_ESCAPES} = 1;
    }
    use Term::Choose qw( choose );

The escape sequences to enable the mouse mode are always hardcoded.

MSWin32¶

If the OS is MSWin32 Win32::Console and Win32::Console::ANSI with ANSI escape sequences are used. See also "codepage_mapping".

SUPPORT¶

You can find documentation for this module with the perldoc command.

    perldoc Term::Choose

AUTHOR¶

Matthäus Kiem <cuer2s@gmail.com>

CREDITS¶

Based on the "choose" function from the Term::Clui module.

Thanks to the Perl-Community.de <http://www.perl-community.de> and the people form stackoverflow <http://stackoverflow.com> for the help.

LICENSE AND COPYRIGHT¶

This library is free software; you can redistribute it and/or modify it under the same terms as Perl 5.10.0. For details, see the full text of the licenses in the file LICENSE.

2021-01-02

perl v5.32.0

Source file:	Term::Choose.3pm.en.gz (from libterm-choose-perl 1.713-1)
Source last updated:	2021-01-02T16:21:36Z
Converted to HTML:	2023-04-09T21:49:55Z