=begin pod

=head1 NAME

Raku port of Perl's hex() / oct() built-ins

=head1 SYNOPSIS

=begin code :lang<raku>
use P5hex; # exports hex() and oct()

print hex '0xAf'; # prints '175'
print hex 'aF';   # same

$val = oct($val) if $val =~ /^0/;
=end code

=head1 DESCRIPTION

This module tries to mimic the behaviour of Perl's C<hex> and C<oct> built-ins
as closely as possible in the Raku Programming Language.

=head1 ORIGINAL PERL 5 DOCUMENTATION

=begin output
hex EXPR
hex     Interprets EXPR as a hex string and returns the corresponding
        value. (To convert strings that might start with either 0, "0x",
        or "0b", see "oct".) If EXPR is omitted, uses $_.

            print hex '0xAf'; # prints '175'
            print hex 'aF';   # same

        Hex strings may only represent integers. Strings that would cause
        integer overflow trigger a warning. Leading whitespace is not
        stripped, unlike oct(). To present something as hex, look into
        "printf", "sprintf", and "unpack".


oct EXPR
oct     Interprets EXPR as an octal string and returns the corresponding
        value. (If EXPR happens to start off with "0x", interprets it as a
        hex string. If EXPR starts off with "0b", it is interpreted as a
        binary string. Leading whitespace is ignored in all three cases.)
        The following will handle decimal, binary, octal, and hex in
        standard Perl notation:

            $val = oct($val) if $val =~ /^0/;

        If EXPR is omitted, uses $_. To go the other way (produce a number
        in octal), use sprintf() or printf():

            $dec_perms = (stat("filename"))[2] & 07777;
            $oct_perm_str = sprintf "%o", $perms;

        The oct() function is commonly used when a string such as 644
        needs to be converted into a file mode, for example. Although Perl
        automatically converts strings into numbers as needed, this
        automatic conversion assumes base 10.

        Leading white space is ignored without warning, as too are any
        trailing non-digits, such as a decimal point ("oct" only handles
        non-negative integers, not negative integers or floating point).
=end output

=head1 PORTING CAVEATS

With the arrival of RakuAST, it has become impossible to access the
topic variable (C<$_>) of the caller's scope.  So Perl's idiom of
calling C<chop> or C<chomp> without arguments has become impossible.
Code such as:

=begin code :lang<raku>
say hex;
=end code

should be changed to either:

=begin code :lang<raku>
say hex($_);
=end code

or, using the subroutine as a method syntax, with the prefix C<.> shortcut
to use that scope's C<$_> as the invocant:

=begin code :lang<raku>
say .&hex;
=end code

=head1 AUTHOR

Elizabeth Mattijsen <liz@raku.rocks>

If you like this module, or what I’m doing more generally, committing to a
L<small sponsorship|https://github.com/sponsors/lizmat/>  would mean a great
deal to me!

Source can be located at: https://github.com/lizmat/P5hex . Comments and
Pull Requests are welcome.

=head1 COPYRIGHT AND LICENSE

Copyright 2018, 2019, 2020, 2021, 2023, 2026 Elizabeth Mattijsen

Re-imagined from Perl as part of the CPAN Butterfly Plan.

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

=end pod

# vim: expandtab shiftwidth=4
