para


module Term::ReadKey:ver<0.0.1> {
  use Term::termios;
  use NativeCall;

  sub getchar returns int32 is native { * }

  sub with-termios(Callable:D $fn, Bool:D :$echo = True --> Str) {
    my $original-flags := Term::termios.new(:fd($*IN.native-descriptor)).getattr;
    my $flags := Term::termios.new(:fd($*IN.native-descriptor)).getattr;

    $flags.unset_lflags('ICANON');
    $flags.unset_lflags('ECHO') unless $echo;
    $flags.setattr(:NOW);

    my $result = $fn();

    $original-flags.setattr(:NOW);

    return $result;
  }

  sub read-character returns Str {
    my Buf $buf .= new;
    my Str $ch = Nil;

    loop {
      # Catch decoding errors and read more bytes until we have a
      # complete/valid UTF-8 sequence.
      CATCH { default { next } }

      $_ != -1 and $ch = $buf.append($_).decode with getchar;

      last;
    }

    return $ch;
  }

  sub read-key(Bool:D :$echo = True --> Str) is export {
    return with-termios(&read-character, :$echo);
  }

  sub key-pressed(Bool:D :$echo = True --> Supply) is export {
    my Supplier $supplier .= new;

    my $done = False;
    my $supply = $supplier.Supply.on-close: { $done = True };

    start {
      with-termios(
        sub {
          until $done {
            my $ch = read-character;

            last if $ch ~~ Nil;

            $supplier.emit($ch);
          }
        },
        :$echo
      );
    }

    return $supply;
  }
}



head

Read single (unbuffered) keys from terminal.


react {
  whenever key-pressed(:!echo) {
    given .fc {
      when 'q' { done }
      default { .uniname.say }
    }
  }
}


Reads one unbuffered (unicode) character from STDIN and returns it as Str or
Nil if nothing could be read. By default the typed character will be echoed to
the terminal unless C<<:!echo>> is passed as argument.


key-pressed(Bool :$echo = True --> Supply)


Returns a supply that emits characters as soon as they're typed (see example in
SYNOPSIS).  The named argument C<<:$echo>> can be used to enable/disable
echoing of the character (on by default).


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


root

README

React

=begin React :component<HeaderCol> :id<menu> 
=para L<Documentation|/doc/introduction>
=para L<Modules| /mods>
=para L<Examples| file:../examples/index.podlite>
=para L<AI|file:../mcp/index.podlite>
=para L<Download |file:../download/index.podlite>
=para L<About|file:../about/index.podlite>
=para 🔍 K<⌘K>/K<ctrl-K>
=end React


=begin React :component<HeaderCol> :id<footer>  
=begin nested :!nested
=item1 B<Language>
    =item2 L<Get started|file:../getting-started/getting-started.podlite>
    =item2 L<Why Raku?|/doc/language/faq#Why-should-I-learn-Raku-What's-so-great-about-it>
    =item2 L<Try Raku|https://glot.io/new/raku>
    =item2 L<Download | file:../download/index.podlite>
    =item2 L<Raku cheat sheet|https://github.com/Raku/mu/blob/master/docs/Perl6/Cheatsheet/cheatsheet.txt>
    =item2 L<Raku on Exercism|https://exercism.org/tracks/raku>
    =item2 L<Wikipedia|https://en.wikipedia.org/wiki/Raku_(programming_language)>

=end nested
=begin nested :!nested

=item1 B<L<Documentation|/doc>>
    =item2 L<Getting started, Migration guides from other languages, & Tutorials | file:../doc/introduction.podlite>
    =item2 L<Language References|file:../doc/reference.podlite>
    =item2 L<Type Reference| file:../doc/types.podlite>
    =item2 L<Miscellaneous| file:../doc/miscellaneous.podlite>
    =item2 L<FAQs (Frequently Asked Questions)|/doc/language/faq>
    =item2 L<Community|/doc/language/community>
    =item2 L<The list of all documents|file:../doc/index.podlite>
    =item2 L<Hand these documents to an AI assistant|file:../mcp/index.podlite>

=end nested
=begin nested :!nested
=item1 B<Learning>
    =item2 L<The Raku Guide|https://raku.guide/>
    =item2 L<Wikibook |https://en.wikibooks.org/wiki/Raku_Programming>
    =item2 L<Books |https://perl6book.com/>
    =item2 L<Rosetta Code | https://www.raku.org/community/rosettacode>
    =item2 L<Learn Raku in Y minutes|https://learnxinyminutes.com/docs/raku/>
    =item2 L<Golfing |https://github.com/AlexDaniel/raku-golf-cheatsheet>
=end nested
=begin nested :!nested

=item1 B<Explore>
    =item2 L<Raku Blog Aggregator|https://planet.raku.org/>
    =item2 L<Rakudo Weekly|https://rakudoweekly.blog/>
    =item2 L<The Weekly Challenge |https://perlweeklychallenge.org/>
    =item2 L<Raku Advent Calendar|https://raku-advent.blog/>

=end nested
=end React


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=para
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=end React


ReadKey

NAME

DESCRIPTION

SYNOPSIS

FUNCTIONS

read-key(Bool :$echo = True --> Str)

key-pressed(Bool :$echo = True --> Supply)

AUTHOR

COPYRIGHT AND LICENSE

Term::ReadKey v0.0.1

Authors

License

Dependencies

Test Dependencies

Provides

Documentation