NAME
Term::Choose - Choose items from a list interactively.
VERSION
Version 1.632
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 ], { justify => 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 withReturn
.choose
then returns the chosen item.If
choose
is called in an list context, the user can also mark an item with theSpaceBar
.choose
then returns - whenReturn
is pressed - the list of marked items (including the highlighted item if the option include_highlighted is set to1
).In list context
Ctrl-SpaceBar
(orCtrl-@
) 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 bychoose
can be closed withReturn
.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-D
) is pressed.
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
the
Arrow
keys (or theh,j,k,l
keys) to move up and down or to move to the right and to the left,the
Tab
key (orCtrl-I
) to move forward, theBackSpace
key (orCtrl-H
orShift-Tab
) to move backward,the
PageUp
key (orCtrl-B
) to go back one page, thePageDown
key (orCtrl-F
) to go forward one page,the
Insert
key to go back 25 pages, theDelete
key to go forward 25 pages,the
Home
key (orCtrl-A
) to jump to the beginning of the list, theEnd
key (orCtrl-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.
beep
0 - off (default)
1 - on
clear_screen
0 - off (default)
1 - clears the screen before printing the choices
color
Setting this option to 1
, 2
or 3
enables the support for color and text formatting escape sequences.
0 - off (default)
1, 2 or 3 - on
How the current position and marked items are highlighted:
1 - only the width of the string is highlighted
2 - the whole column width is highlighted, the cursor keeps the default color
3 - the whole column width is highlighted, the cursor takes the color of the string
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>")
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 string 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.
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
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
.----------------------. .----------------------. .----------------------. .----------------------. | .. | | .. | | .. | | .. | | .. | | .. | | .. | | .. | | .. | | .. | | .. | | .. | | | | .. | | .. | | .. | | | | | | .. | | .. | | | | | | | | .. | '----------------------' '----------------------' '----------------------' '----------------------'
lf
If prompt lines are folded the option lf allows one 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: undefined)
ll
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 the value of ll is greater than the screen width, choose
returns immediately -2
.
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
For MSWin32 see also 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)
. This doesn't apply if the OS is MSWin32.
If the OS is MSWin32 there is no difference between the mouse modes 1, 3, and 4 - the all enable the mouse 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
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
It is required a terminal that supports ANSI escape sequences.
If the option "hide_cursor" is enabled, it is also required the support for the following escape sequences:
"\e[?25l" Hide Cursor
"\e[?25h" Show Cursor
If a mouse mode is enabled
"\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.
If the OS is MSWin32 Win32::Console is used, to emulate the behavior of the escape sequences. If the option color is enabled, Win32::Console::ANSI is loaded to translate the color and text formatting escape sequences.
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 and the people form stackoverflow for the help.
LICENSE AND COPYRIGHT
Copyright (C) 2012-2018 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.