NAME

Term::Choose - Choose items from a list.

VERSION

Version 1.101

SYNOPSIS

use 5.10.1;
use Term::Choose qw(choose);

my $array_ref = [ qw( one two three four five ) ];

my $choice = choose( $array_ref );                            # single choice
say $choice;

my @choices = choose( [ 1 .. 100 ], { justify => 1 } );       # multiple choice
say "@choices";

choose( [ 'Press ENTER to continue' ], { prompt => '' } );    # no choice

# or OO-interface

use 5.10.1;
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
say $choice;

$new->config( { justify => 1 } )
my @choices = $new->choose( [ 1 .. 100 ] );                    # multiple choice
say "@choices";

my $stopp = Term::Choose->new( { prompt => '' } )
$stopp->choose( [ 'Press ENTER to continue' ] );               # no choice

DESCRIPTION

Choose from a list of items.

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

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.

The argument - a reference to a hash of "option-key => option-value" pairs - is optional.

For detailed information about the options see "OPTIONS".

config

$new->config( \%options );

This method expects a hash reference as its argument.

The method config sets the different options.

For detailed information about the different options, their allowed and default values 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.

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

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

          $new->choose( $array_ref [, \%options] );

The array the reference refers to is called in the documentation simply array or list respective elements (of the array).

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

SUBROUTINES

choose

The function choose allows 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 "move-around-keys" and confirming with c<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.

    In list context Ctrl-SpaceBar 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 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. In list context marked items are reset.

The q key (or Ctrl-D) returns undef or an empty list in list context.

With a mouse mode enabled (and if supported by the terminal) the 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:

  • Arrow keys (or hjkl),

  • Tab key (or Ctrl-I) to move forward, BackSpace key (or Ctrl-H or Shift-Tab) to move backward,

  • PageUp key (or Ctrl-B) to go back one page, PageDown key (or Ctrl-F) to go forward one page,

  • Home key (or Ctrl-A) to jump to the beginning of the list, 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:

  • 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.

  • white-spaces in elements are replaced with simple spaces.

    $element =~ s/\p{Space}/ /g;
  • characters which match the Unicode character property Other are removed.

    $element =~ s/\p{C}//g;
  • if the length of an element is greater than the width of the screen the element is cut.

    $element = substr( $element, 0, $allowed_length - 3 ) . '...';*

    * Term::Choose uses its own function to cut strings which uses print columns for the arithmetic.

All these 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.

OPTIONS

Options which expect a number as their value expect integers.

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'

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

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

max_height

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

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

Height in this context means print rows.

max_height overwrites keep if max_height is set and less than keep.

Allowed values: 1 or greater

(default: undef)

max_width

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

Width refers here to the number of print columns.

Allowed values: 1 or greater

(default: undef)

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.

justify

0 - elements ordered in columns are left justified (default)

1 - elements ordered in columns are right justified

2 - elements ordered in columns are centered

pad

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

Allowed values: 0 or greater

pad_one_row

Sets the number of whitespaces between elements if we have only one row. (default: value of the option pad)

Allowed values: 0 or greater

clear_screen

0 - off (default)

1 - clears the screen before printing the choices

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: undef)

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.

page

0 - off

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

mouse

The following is valid if the OS is not MSWin32. For MSWin32 see the end of this section.

0 - no mouse mode (default)

1 - mouse mode 1003 enabled

2 - mouse mode 1003 enabled; the output width is limited to 223 print-columns and the height to 223 rows (mouse mode 1003 doesn't work above 223)

3 - extended mouse mode (1005) - uses utf8

4 - extended SGR mouse mode (1006)

If a mouse mode is enabled layers for STDIN are changed. Then before leaving choose as a cleanup STDIN is marked as UTF-8 with :encoding(UTF-8).

If the OS is MSWin32 1, 3 and 4 enable the mouse and are equivalent. The mouse mode 2 enables also the mouse but the output width is limited to 223 print-columns and the output height is limited to 223 rows. The mouse mode 0 disables the mouse (default).

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)

beep

0 - off (default)

1 - on

hide_cursor

0 - keep the terminals highlighting of the cursor position

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

limit

Sets the maximal allowed length of the array. (default: undef)

If the array referred by the first argument has more than limit elements choose uses only the first limit array elements.

Allowed values: 1 or greater

undef

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

default: '<undef>'

empty

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

default: '<empty>'

lf

If prompt lines are folded the option lf allows to insert spaces at beginning of the folded lines.

The option lf 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 for the two elements are: 0 or greater.

See INITIAL_TAB and SUBSEQUENT_TAB in Text::LineFold.

(default: undef)

ll

If all elements have the same length and this length is known before calling choose the length can be passed with this option.

If ll is set, then choose doesn't calculate the length of the longest element itself but uses the value passed with this option.

length refers here to the number of print columns the element will use on the terminal.

A way to determine the number of print columns is the use of columns from Unicode::GCString.

The length of undefined elements and elements with an empty string depends on the value of the option undef respective on the value of the option empty.

If the option ll is set the replacements described in "Modifications for the output" are not applied.

If elements contain unsupported characters the output might break if the width (number of print columns) of the replacement character does not correspond to the width of the replaced character - for example when a unsupported non-spacing character is replaced by a replacement character with a normal width.

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

If the value of ll is greater than the screen width the elements will be trimmed to fit into the screen.

Allowed values: 1 or greater

(default: undef)

ERROR HANDLING

croak

  • If passed an invalid number of arguments to a method/function it dies.

  • If passed an invalid argument to a method/function it dies.

carp

  • If the array referred by the first argument is empty choose warns and returns undef respective an empty list.

  • If an option does not exist new|config|choose warns.

  • If an option value is not valid new|config|choose warns and the default is used instead.

  • If after pressing a key Term::ReadKey::ReadKey returns undef (choose warns with "EOT: $!" and returns undef or an empty list in list context).

REQUIREMENTS

Perl version

Requires Perl version 5.10.1 or greater.

Modules

Used modules not provided as core modules:

If the OS is MSWin32 the following module are required additionally

else

required.

Decoded strings

choose expects decoded strings as array elements.

encoding layer for STDOUT

For a correct output it is required to set an 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.

Escape sequences

The following ANSI escape sequences are used:

"\e[A"      Cursor Up

"\e[C"      Cursor Forward

"\e[0J"     Clear to End of Screen (Erase Data)

"\e[0m"     Normal/Reset

"\e[1m"     Bold

"\e[4m"     Underline

"\e[7m"     Inverse

If the option "hide_cursor" is enabled:

"\e[?25l"   Hide Cursor

"\e[?25h"   Show Cursor

If the option "clear_screen" is enabled:

"\e[2J"     Clear Screen (Erase Data)

"\e[1;1H"   Go to Top Left (Cursor Position)

If the OS is MSWin32 the Win32::Console::ANSI module is used to understand these escape sequences.

If a "mouse" mode is enabled

"\e[6n"    Get Cursor Position (Device Status Report)

"\e[?1003h", "\e[?1005h", "\e[?1006h"   Enable Mouse Tracking

"\e[?1003l", "\e[?1005l", "\e[?1006l"   Disable Mouse Tracking

are used to enable/disable the different mouse modes.

To read key and mouse events with MSWin32 Win32::Console is used instead.

SUPPORT

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

perldoc Term::Choose

AUTHOR

Matthäus Kiem <cuer2s@gmail.com>

CREDITS

Based on and inspired by the choose function from the Term::Clui module.

Thanks to the Perl-Community.de and the people form stackoverflow for the help.

LICENSE AND COPYRIGHT

Copyright (C) 2012-2014 Matthäus Kiem.

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.