


Term::UI(3p)     Perl Programmers Reference Guide    Term::UI(3p)


NAME
       Term::UI - Term::ReadLine UI made easy

SYNOPSIS
           use Term::UI;
           use Term::ReadLine;

           my $term = Term::ReadLine->new('brand');

           my $reply = $term->get_reply(
                           prompt => 'What is your favourite colour?',
                           choices => [qw|blue red green|],
                           default => blue,
           );

           my $bool = $term->ask_yn(
                               prompt => 'Do you like cookies?',
                               default => 'y',
                       );


           my $string = q[some_command -option --no-foo --quux='this thing'];

           my ($options,$munged_input) = $term->parse_options($string);


           ### don't have Term::UI issue warnings -- default is '1'
           $Term::UI::VERBOSE = 0;

           ### always pick the default (good for non-interactive terms)
           ### -- default is '0'
           $Term::UI::AUTOREPLY = 1;

           ### Retrieve the entire session as a printable string:
           $hist = Term::UI::History->history_as_string;
           $hist = $term->history_as_string;

DESCRIPTION
       "Term::UI" is a transparent way of eliminating the
       overhead of having to format a question and then validate
       the reply, informing the user if the answer was not proper
       and re-issuing the question.

       Simply give it the question you want to ask, optionally
       with choices the user can pick from and a default and
       "Term::UI" will DWYM.

       For asking a yes or no question, there's even a shortcut.

HOW IT WORKS
       "Term::UI" places itself at the back of the
       "Term::ReadLine" @ISA array, so you can call its functions
       through your term object.




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       "Term::UI" uses "Term::UI::History" to record all
       interactions with the commandline. You can retrieve this
       history, or alter the filehandle the interaction is
       printed to. See the "Term::UI::History" manpage or the
       "SYNOPSIS" for details.

METHODS
   $reply = $term->get_reply( prompt => 'question?', [choices =>
       \@list, default => $list[0], multi => BOOL, print_me =>
       "extra text to print & record", allow => $ref] );
       "get_reply" asks a user a question, and then returns the
       reply to the caller. If the answer is invalid (more on
       that below), the question will be reposed, until a
       satisfactory answer has been entered.

       You have the option of providing a list of choices the
       user can pick from using the "choices" argument. If the
       answer is not in the list of choices presented, the
       question will be reposed.

       If you provide a "default"  answer, this will be returned
       when either $AUTOREPLY is set to true, (see the "GLOBAL
       VARIABLES" section further below), or when the user just
       hits "enter".

       You can indicate that the user is allowed to enter
       multiple answers by toggling the "multi" flag. Note that a
       list of answers will then be returned to you, rather than
       a simple string.

       By specifying an "allow" hander, you can yourself validate
       the answer a user gives. This can be any of the types that
       the Params::Check "allow" function allows, so please refer
       to that manpage for details.

       Finally, you have the option of adding a "print_me"
       argument, which is simply printed before the prompt. It's
       printed to the same file handle as the rest of the
       questions, so you can use this to keep track of a full
       session of Q&A with the user, and retrieve it later using
       the "Term::UI->history_as_string" function.

       See the "EXAMPLES" section for samples of how to use this
       function.

   $bool = $term->ask_yn( prompt => "your question", [default =>
       (y|1,n|0), print_me => "extra text to print & record"] )
       Asks a simple "yes" or "no" question to the user,
       returning a boolean indicating "true" or "false" to the
       caller.

       The "default" answer will automatically returned, if the
       user hits "enter" or if $AUTOREPLY is set to true. See the
       "GLOBAL VARIABLES" section further below.



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       Also, you have the option of adding a "print_me" argument,
       which is simply printed before the prompt. It's printed to
       the same file handle as the rest of the questions, so you
       can use this to keep track of a full session of Q&A with
       the user, and retrieve it later using the
       "Term::UI->history_as_string" function.

       See the "EXAMPLES" section for samples of how to use this
       function.

   ($opts, $munged) = $term->parse_options( STRING );
       "parse_options" will convert all options given from an
       input string to a hash reference. If called in list
       context it will also return the part of the input string
       that it found no options in.

       Consider this example:

           my $str =   q[command --no-foo --baz --bar=0 --quux=bleh ] .
                       q[--option="some'thing" -one-dash -single=blah' arg];

           my ($options,$munged) =  $term->parse_options($str);

           ### $options would contain: ###
           $options = {
                       'foo'       => 0,
                       'bar'       => 0,
                       'one-dash'  => 1,
                       'baz'       => 1,
                       'quux'      => 'bleh',
                       'single'    => 'blah\'',
                       'option'    => 'some\'thing'
           };

           ### and this is the munged version of the input string,
           ### ie what's left of the input minus the options
           $munged = 'command arg';

       As you can see, you can either use a single or a double
       "-" to indicate an option.  If you prefix an option with
       "no-" and do not give it a value, it will be set to 0.  If
       it has no prefix and no value, it will be set to 1.
       Otherwise, it will be set to its value. Note also that it
       can deal fine with single/double quoting issues.

   $str = $term->history_as_string
       Convenience wrapper around
       "Term::UI::History->history_as_string".

       Consult the "Term::UI::History" man page for details.

GLOBAL VARIABLES
       The behaviour of Term::UI can be altered by changing the
       following global variables:



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   $Term::UI::VERBOSE
       This controls whether Term::UI will issue warnings and
       explanations as to why certain things may have failed. If
       you set it to 0, Term::UI will not output any warnings.
       The default is 1;

   $Term::UI::AUTOREPLY
       This will make every question be answered by the default,
       and warn if there was no default provided. This is
       particularly useful if your program is run in non-
       interactive mode.  The default is 0;

   $Term::UI::INVALID
       This holds the string that will be printed when the user
       makes an invalid choice.  You can override this string
       from your program if you, for example, wish to do
       localization.  The default is "Invalid selection, please
       try again: "

   $Term::UI::History::HISTORY_FH
       This is the filehandle all the print statements from this
       module are being sent to. Please consult the
       "Term::UI::History" manpage for details.

       This defaults to *STDOUT.

EXAMPLES
   Basic get_reply sample
           ### ask a user (with an open question) for their favourite colour
           $reply = $term->get_reply( prompt => 'Your favourite colour? );

       which would look like:

           Your favourite colour?

       and $reply would hold the text the user typed.

   get_reply with choices
           ### now provide a list of choices, so the user has to pick one
           $reply = $term->get_reply(
                       prompt  => 'Your favourite colour?',
                       choices => [qw|red green blue|] );

       which would look like:

             1> red
             2> green
             3> blue

           Your favourite colour?

       $reply will hold one of the choices presented. "Term::UI"
       will repose the question if the user attempts to enter an
       answer that's not in the list of choices. The string



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       presented is held in the $Term::UI::INVALID variable (see
       the "GLOBAL VARIABLES" section for details.

   get_reply with choices and default
           ### provide a sensible default option -- everyone loves blue!
           $reply = $term->get_reply(
                       prompt  => 'Your favourite colour?',
                       choices => [qw|red green blue|],
                       default => 'blue' );

       which would look like:

             1> red
             2> green
             3> blue

           Your favourite colour? [3]:

       Note the default answer after the prompt. A user can now
       just hit "enter" (or set $Term::UI::AUTOREPLY -- see the
       "GLOBAL VARIABLES" section) and the sensible answer 'blue'
       will be returned.

   get_reply using print_me & multi
           ### allow the user to pick more than one colour and add an
           ### introduction text
           @reply = $term->get_reply(
                       print_me    => 'Tell us what colours you like',
                       prompt      => 'Your favourite colours?',
                       choices     => [qw|red green blue|],
                       multi       => 1 );

       which would look like:

           Tell us what colours you like
             1> red
             2> green
             3> blue

           Your favourite colours?

       An answer of "3 2 1" would fill @reply with "blue green
       red"

   get_reply & allow
           ### pose an open question, but do a custom verification on
           ### the answer, which will only exit the question loop, if
           ### the answer matches the allow handler.
           $reply = $term->get_reply(
                       prompt  => "What is the magic number?",
                       allow   => 42 );

       Unless the user now enters 42, the question will be
       reposed over and over again. You can use more



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Term::UI(3p)     Perl Programmers Reference Guide    Term::UI(3p)


       sophisticated "allow" handlers (even subroutines can be
       used). The "allow" handler is implemented using
       "Params::Check"'s "allow" function. Check its manpage for
       details.

   an elaborate ask_yn sample
           ### ask a user if he likes cookies. Default to a sensible 'yes'
           ### and inform him first what cookies are.
           $bool = $term->ask_yn( prompt   => 'Do you like cookies?',
                                  default  => 'y',
                                  print_me => 'Cookies are LOVELY!!!' );

       would print:

           Cookies are LOVELY!!!
           Do you like cookies? [Y/n]:

       If a user then simply hits "enter", agreeing with the
       default, $bool would be set to "true". (Simply hitting 'y'
       would also return "true". Hitting 'n' would return
       "false")

       We could later retrieve this interaction by printing out
       the Q&A history as follows:

           print $term->history_as_string;

       which would then print:

           Cookies are LOVELY!!!
           Do you like cookies? [Y/n]:  y

       There's a chance we're doing this non-interactively,
       because a console is missing, the user indicated he just
       wanted the defaults, etc.

       In this case, simply setting $Term::UI::AUTOREPLY to true,
       will return from every question with the default answer
       set for the question.  Do note that if "AUTOREPLY" is
       true, and no default is set, "Term::UI" will warn about
       this and return "undef".

See Also
       "Params::Check", "Term::ReadLine", "Term::UI::History"

BUG REPORTS
       Please report bugs or other issues to
       <bug-term-ui@rt.cpan.org<gt>.

AUTHOR
       This module by Jos Boumans <kane@cpan.org>.

COPYRIGHT
       This library is free software; you may redistribute and/or



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       modify it under the same terms as Perl itself.
























































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