package PPI::Token::Number::Exp;
=pod
=head1 NAME
PPI::Token::Number::Exp - Token class for an exponential notation number
=head1 SYNOPSIS
$n = 1.0e-2;
$n = 1e+2;
=head1 INHERITANCE
PPI::Token::Number::Exp
isa PPI::Token::Number::Float
isa PPI::Token::Number
isa PPI::Token
isa PPI::Element
=head1 DESCRIPTION
The C<PPI::Token::Number::Exp> class is used for tokens that
represent floating point numbers with exponential notation.
=head1 METHODS
=cut
use strict;
use PPI::Token::Number::Float ();
use vars qw{$VERSION @ISA};
BEGIN {
$VERSION = '1.218';
@ISA = 'PPI::Token::Number::Float';
}
=pod
=head2 literal
Return the numeric value of this token.
=cut
sub literal {
my $self = shift;
return if $self->{_error};
my ($mantissa, $exponent) = split m/e/i, $self->_literal;
my $neg = $mantissa =~ s/^\-//;
$mantissa =~ s/^\./0./;
$exponent =~ s/^\+//;
my $val = $mantissa * 10 ** $exponent;
return $neg ? -$val : $val;
}
#####################################################################
# Tokenizer Methods
sub __TOKENIZER__on_char {
my $class = shift;
my $t = shift;
my $char = substr( $t->{line}, $t->{line_cursor}, 1 );
# To get here, the token must have already encountered an 'E'
# Allow underscores straight through
return 1 if $char eq '_';
# Allow digits
return 1 if $char =~ /\d/o;
# Start of exponent is special
if ( $t->{token}->{content} =~ /e$/i ) {
# Allow leading +/- in exponent
return 1 if $char eq '-' || $char eq '+';
# Invalid character in exponent. Recover
if ( $t->{token}->{content} =~ s/\.(e)$//i ) {
my $word = $1;
$t->{class} = $t->{token}->set_class('Number');
$t->_new_token('Operator', '.');
$t->_new_token('Word', $word);
return $t->{class}->__TOKENIZER__on_char( $t );
}
else {
$t->{token}->{_error} = "Illegal character in exponent '$char'";
}
}
# Doesn't fit a special case, or is after the end of the token
# End of token.
$t->_finalize_token->__TOKENIZER__on_char( $t );
}
1;
=pod
=head1 SUPPORT
See the L<support section|PPI/SUPPORT> in the main module.
=head1 AUTHOR
Chris Dolan E<lt>cdolan@cpan.orgE<gt>
=head1 COPYRIGHT
Copyright 2006 Chris Dolan.
This program is free software; you can redistribute
it and/or modify it under the same terms as Perl itself.
The full text of the license can be found in the
LICENSE file included with this module.
=cut