use vars qw($VERSION);
use Carp;
-$VERSION = '2.06';
+$VERSION = '2.091';
# LOAD FILTERING MODULE...
sub import
{
- $DB::single = 1;
$fallthrough = grep /\bfallthrough\b/, @_;
$offset = (caller)[2]+1;
filter_add({}) unless @_>1 && $_[1] eq 'noimport';
return $status if $status<0;
$_ = filter_blocks($_,$offset);
$_ = "# line $offset\n" . $_ if $offset; undef $offset;
- # print STDERR $_;
return $status;
}
|| $Perl6 && $source =~ /when|given/;
pos $source = 0;
my $text = "";
+ $DB::single = 1;
component: while (pos $source < length $source)
{
if ($source =~ m/(\G\s*use\s+Switch\b)/gc)
my @pos = Text::Balanced::_match_quotelike(\$source,qr/\s*/,1,0);
if (defined $pos[0])
{
- $text .= " " . substr($source,$pos[2],$pos[18]-$pos[2]);
+ $text .= " " if $pos[0] < $pos[2];
+ $text .= substr($source,$pos[2],$pos[18]-$pos[2]);
next component;
}
if ($source =~ m/\G\s*($pod_or_DATA)/gc) {
@pos = Text::Balanced::_match_variable(\$source,qr/\s*/);
if (defined $pos[0])
{
- $text .= " " . substr($source,$pos[0],$pos[4]-$pos[0]);
+ $text .= " " if $pos[0] < $pos[2];
+ $text .= substr($source,$pos[0],$pos[4]-$pos[0]);
next component;
}
if ($Perl5 && $source =~ m/\G(\n*)(\s*)(switch)\b(?=\s*[(])/gc
- || $Perl6 && $source =~ m/\G(\n*)(\s*)(given)\b(?=\s*[(])/gc)
+ || $Perl6 && $source =~ m/\G(\n*)(\s*)(given)\b(?=\s*[(])/gc
+ || $Perl6 && $source =~ m/\G(\n*)(\s*)(given)\b(.*)(?=\{)/gc)
{
my $keyword = $3;
+ my $arg = $4;
+ # print STDERR "[$arg]\n";
$text .= $1.$2.'S_W_I_T_C_H: while (1) ';
- @pos = Text::Balanced::_match_codeblock(\$source,qr/\s*/,qr/\(/,qr/\)/,qr/[[{(<]/,qr/[]})>]/,undef)
- or do {
- die "Bad $keyword statement (problem in the parentheses?) near $Switch::file line ", line(substr($source,0,pos $source),$line), "\n";
- };
- my $arg = filter_blocks(substr($source,$pos[0],$pos[4]-$pos[0]),line(substr($source,0,$pos[0]),$line));
+ unless ($arg) {
+ @pos = Text::Balanced::_match_codeblock(\$source,qr/\s*/,qr/\(/,qr/\)/,qr/[[{(<]/,qr/[]})>]/,undef)
+ or do {
+ die "Bad $keyword statement (problem in the parentheses?) near $Switch::file line ", line(substr($source,0,pos $source),$line), "\n";
+ };
+ $arg = filter_blocks(substr($source,$pos[0],$pos[4]-$pos[0]),line(substr($source,0,$pos[0]),$line));
+ }
$arg =~ s {^\s*[(]\s*%} { ( \\\%} ||
$arg =~ s {^\s*[(]\s*m\b} { ( qr} ||
$arg =~ s {^\s*[(]\s*/} { ( qr/} ||
$text .= $1."if (Switch::case";
if (@pos = Text::Balanced::_match_codeblock(\$source,qr/\s*/,qr/\{/,qr/\}/,qr/\{/,qr/\}/,undef)) {
my $code = substr($source,$pos[0],$pos[4]-$pos[0]);
- $text .= " sub" if is_block $code;
- $text .= " " . filter_blocks($code,line(substr($source,0,$pos[0]),$line)) . ")";
+ $text .= " " if $pos[0] < $pos[2];
+ $text .= "sub " if is_block $code;
+ $text .= filter_blocks($code,line(substr($source,0,$pos[0]),$line)) . ")";
}
elsif (@pos = Text::Balanced::_match_codeblock(\$source,qr/\s*/,qr/[[(]/,qr/[])]/,qr/[[({]/,qr/[])}]/,undef)) {
my $code = filter_blocks(substr($source,$pos[0],$pos[4]-$pos[0]),line(substr($source,0,$pos[0]),$line));
$code =~ s {^\s*[(]\s*m\b} { ( qr} ||
$code =~ s {^\s*[(]\s*/} { ( qr/} ||
$code =~ s {^\s*[(]\s*qw} { ( \\qw};
- $text .= " $code)";
+ $text .= " " if $pos[0] < $pos[2];
+ $text .= "$code)";
}
elsif ($Perl6 && do{@pos = Text::Balanced::_match_variable(\$source,qr/\s*/)}) {
my $code = filter_blocks(substr($source,$pos[0],$pos[4]-$pos[0]),line(substr($source,0,$pos[0]),$line));
$code =~ s {^\s*%} { \%} ||
$code =~ s {^\s*@} { \@};
- $text .= " $code)";
+ $text .= " " if $pos[0] < $pos[2];
+ $text .= "$code)";
}
elsif ( @pos = Text::Balanced::_match_quotelike(\$source,qr/\s*/,1,0)) {
my $code = substr($source,$pos[2],$pos[18]-$pos[2]);
$code =~ s {^\s*m} { qr} ||
$code =~ s {^\s*/} { qr/} ||
$code =~ s {^\s*qw} { \\qw};
- $text .= " $code)";
+ $text .= " " if $pos[0] < $pos[2];
+ $text .= "$code)";
}
elsif ($Perl5 && $source =~ m/\G\s*(([^\$\@{])[^\$\@{]*)(?=\s*{)/gc
- || $Perl6 && $source =~ m/\G\s*([^:;]*)()/gc) {
+ || $Perl6 && $source =~ m/\G\s*([^;{]*)()/gc) {
my $code = filter_blocks($1,line(substr($source,0,pos $source),$line));
$text .= ' \\' if $2 eq '%';
$text .= " $code)";
die "Bad $keyword statement (invalid $keyword value?) near $Switch::file line ", line(substr($source,0,pos $source), $line), "\n";
}
- die "Missing colon or semi-colon after 'when' value near $Switch::file line ", line(substr($source,0,pos $source), $line), "\n"
- unless !$Perl6 || $source =~ m/\G(\s*)(:|(?=;))/gc;
+ die "Missing opening brace or semi-colon after 'when' value near $Switch::file line ", line(substr($source,0,pos $source), $line), "\n"
+ unless !$Perl6 || $source =~ m/\G(\s*)(?=;|\{)/gc;
do{@pos = Text::Balanced::_match_codeblock(\$source,qr/\s*/,qr/\{/,qr/\}/,qr/\{/,qr/\}/,undef)}
or do {
=head1 VERSION
-This document describes version 2.06 of Switch,
-released November 14, 2001.
+This document describes version 2.09 of Switch,
+released June 12, 2002.
=head1 SYNOPSIS
Perl 6 will provide a built-in switch statement with essentially the
same semantics as those offered by Switch.pm, but with a different
-pair of keywords. In Perl 6 C<switch> with be spelled C<given>, and
+pair of keywords. In Perl 6 C<switch> will be spelled C<given>, and
C<case> will be pronounced C<when>. In addition, the C<when> statement
-will use a colon between its case value and its block (removing the
-need to parenthesize variables.
+will not require switch or case values to be parenthesized.
-This future syntax is also available via the Switch.pm module, by
+This future syntax is also (largely) available via the Switch.pm module, by
importing it with the argument C<"Perl6">. For example:
use Switch 'Perl6';
given ($val) {
- when 1 : { handle_num_1(); }
- when $str1 : { handle_str_1(); }
- when [0..9] : { handle_num_any(); last }
- when /\d/ : { handle_dig_any(); }
- when /.*/ : { handle_str_any(); }
+ when 1 { handle_num_1(); }
+ when ($str1) { handle_str_1(); }
+ when [0..9] { handle_num_any(); last }
+ when /\d/ { handle_dig_any(); }
+ when /.*/ { handle_str_any(); }
}
-Note that you can mix and match both syntaxes by importing the module
+Note that scalars still need to be parenthesized, since they would be
+ambiguous in Perl 5.
+
+Note too that you can mix and match both syntaxes by importing the module
with:
use Switch 'Perl5', 'Perl6';