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use strict;
package String::Flogger 1.101246;
# ABSTRACT: string munging for loggers
use Params::Util qw(_ARRAYLIKE _CODELIKE);
use Scalar::Util qw(blessed);
use Sub::Exporter -setup => [ flog => Sub::Exporter::Util::curry_method ];
#pod =head1 SYNOPSIS
#pod
#pod use String::Flogger qw(flog);
#pod
#pod my @inputs = (
#pod 'simple!',
#pod
#pod [ 'slightly %s complex', 'more' ],
#pod
#pod [ 'and inline some data: %s', { look => 'data!' } ],
#pod
#pod [ 'and we can defer evaluation of %s if we want', sub { 'stuff' } ],
#pod
#pod sub { 'while avoiding sprintfiness, if needed' },
#pod );
#pod
#pod say flog($_) for @inputs;
#pod
#pod The above will output:
#pod
#pod simple!
#pod
#pod slightly more complex
#pod
#pod and inline some data: {{{ "look": "data!" }}}
#pod
#pod and we can defer evaluation of stuff if we want
#pod
#pod while avoiding sprintfiness, if needed
#pod
#pod =method flog
#pod
#pod This method is described in the synopsis.
#pod
#pod =method format_string
#pod
#pod $flogger->format_string($fmt, \@input);
#pod
#pod This method is used to take the formatted arguments for a format string (when
#pod C<flog> is passed an arrayref) and turn it into a string. By default, it just
#pod uses C<L<perlfunc/sprintf>>.
#pod
#pod =cut
sub _encrefs {
my ($self, $messages) = @_;
return map { blessed($_) ? sprintf('obj(%s)', "$_")
: ref $_ ? $self->_stringify_ref($_)
: defined $_ ? $_
: '{{null}}' }
map { _CODELIKE($_) ? scalar $_->() : $_ }
@$messages;
}
my $JSON;
sub _stringify_ref {
my ($self, $ref) = @_;
if (ref $ref eq 'SCALAR' or ref $ref eq 'REF') {
my ($str) = $self->_encrefs([ $$ref ]);
return "ref($str)";
}
require JSON::MaybeXS;
$JSON ||= JSON::MaybeXS->new
->ascii(1)
->canonical(1)
->allow_nonref(1)
->space_after(1)
->convert_blessed(1);
# This is horrible. Just horrible. I wish I could do this with a callback
# -- rjbs, 2013-01-31
local *UNIVERSAL::TO_JSON = sub { "obj($_[0])" };
return '{{' . $JSON->encode($ref) . '}}'
}
sub flog {
my ($class, $input) = @_;
my $output;
if (_CODELIKE($input)) {
$input = $input->();
}
return $input unless ref $input;
if (_ARRAYLIKE($input)) {
my ($fmt, @data) = @$input;
return $class->format_string($fmt, $class->_encrefs(\@data));
}
return $class->format_string('%s', $class->_encrefs([$input]));
}
sub format_string {
my ($self, $fmt, @input) = @_;
sprintf $fmt, @input;
}
1;
__END__
=pod
=encoding UTF-8
=head1 NAME
String::Flogger - string munging for loggers
=head1 VERSION
version 1.101246
=head1 SYNOPSIS
use String::Flogger qw(flog);
my @inputs = (
'simple!',
[ 'slightly %s complex', 'more' ],
[ 'and inline some data: %s', { look => 'data!' } ],
[ 'and we can defer evaluation of %s if we want', sub { 'stuff' } ],
sub { 'while avoiding sprintfiness, if needed' },
);
say flog($_) for @inputs;
The above will output:
simple!
slightly more complex
and inline some data: {{{ "look": "data!" }}}
and we can defer evaluation of stuff if we want
while avoiding sprintfiness, if needed
=head1 PERL VERSION
This module should work on any version of perl still receiving updates from
the Perl 5 Porters. This means it should work on any version of perl released
in the last two to three years. (That is, if the most recently released
version is v5.40, then this module should work on both v5.40 and v5.38.)
Although it may work on older versions of perl, no guarantee is made that the
minimum required version will not be increased. The version may be increased
for any reason, and there is no promise that patches will be accepted to lower
the minimum required perl.
=head1 METHODS
=head2 flog
This method is described in the synopsis.
=head2 format_string
$flogger->format_string($fmt, \@input);
This method is used to take the formatted arguments for a format string (when
C<flog> is passed an arrayref) and turn it into a string. By default, it just
uses C<L<perlfunc/sprintf>>.
=head1 AUTHOR
Ricardo SIGNES <cpan@semiotic.systems>
=head1 CONTRIBUTORS
=for stopwords Randy Stauner Ricardo Signes
=over 4
=item *
Randy Stauner <randy@magnificent-tears.com>
=item *
Ricardo Signes <rjbs@semiotic.systems>
=back
=head1 COPYRIGHT AND LICENSE
This software is copyright (c) 2022 by Ricardo Signes.
This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.
=cut