Perl's “Switch” grabs a 'case' string inside a HERE document and gets confused?
I have a little Perl code, with a HERE document. Inside the HERE document's text, there is embedded the keyword case. This seems to unnerve the Switch statement mightily. Am I crazy?
#!/usr/bin/perl
use strict;
use warnings;
use utf8; # Meaning "This lexical scope (i.e. file) contains utf8"
use Switch;
sub printUsage transaction end.
+
HERE
Running this in Perl 5.16 gives:
Bad case statement (invalid case value?) near avo2.pl line 13
i.e. In case of isn't appreciated "here", literally. Some bug? Should I raise this at the Perl bug tracker?
perl
asked Nov 12 '18 at 13:59
David TonhoferDavid Tonhofer
5,41513431
add a comment |
I have a little Perl code, with a HERE document. Inside the HERE document's text, there is embedded the keyword case. This seems to unnerve the Switch statement mightily. Am I crazy?
#!/usr/bin/perl
use strict;
use warnings;
use utf8; # Meaning "This lexical scope (i.e. file) contains utf8"
use Switch;
sub printUsage transaction end.
+
HERE
Running this in Perl 5.16 gives:
Bad case statement (invalid case value?) near avo2.pl line 13
i.e. In case of isn't appreciated "here", literally. Some bug? Should I raise this at the Perl bug tracker?
perl
asked Nov 12 '18 at 13:59
David TonhoferDavid Tonhofer
5,41513431
6
The general advice is to avoidSwitchbecause, according to its POD... "There are undoubtedly serious bugs lurking somewhere in code this funky"
– toolic
Nov 12 '18 at 14:01
4
The POD on CPAN (metacpan.org/pod/Switch#BUGS) even lists this as a known bug: "On perl 5.10.x may cause syntax error if "case" is present inside heredoc.".
– toolic
Nov 12 '18 at 14:09
4
Switch is a source filter, which means it must parse the Perl code that follows itself. An impossible feat, so it doesn't really actually try. You get errors such as the one you describe, and they can be very hard to debug. Avoid Switch.
– ikegami
Nov 12 '18 at 14:24
add a comment |
I have a little Perl code, with a HERE document. Inside the HERE document's text, there is embedded the keyword case. This seems to unnerve the Switch statement mightily. Am I crazy?
#!/usr/bin/perl
use strict;
use warnings;
use utf8; # Meaning "This lexical scope (i.e. file) contains utf8"
use Switch;
sub printUsage transaction end.
+
HERE
Running this in Perl 5.16 gives:
Bad case statement (invalid case value?) near avo2.pl line 13
i.e. In case of isn't appreciated "here", literally. Some bug? Should I raise this at the Perl bug tracker?
perl
asked Nov 12 '18 at 13:59
David TonhoferDavid Tonhofer
5,41513431
I have a little Perl code, with a HERE document. Inside the HERE document's text, there is embedded the keyword case. This seems to unnerve the Switch statement mightily. Am I crazy?
#!/usr/bin/perl
use strict;
use warnings;
use utf8; # Meaning "This lexical scope (i.e. file) contains utf8"
use Switch;
sub printUsage transaction end.
+
HERE
Running this in Perl 5.16 gives:
Bad case statement (invalid case value?) near avo2.pl line 13
i.e. In case of isn't appreciated "here", literally. Some bug? Should I raise this at the Perl bug tracker?
perl
perl
asked Nov 12 '18 at 13:59
David TonhoferDavid Tonhofer
5,41513431
asked Nov 12 '18 at 13:59
David TonhoferDavid Tonhofer
5,41513431
edited Nov 12 '18 at 16:05
David Tonhofer
asked Nov 12 '18 at 13:59
David TonhoferDavid Tonhofer
5,41513431
asked Nov 12 '18 at 13:59
David TonhoferDavid Tonhofer
5,41513431
asked Nov 12 '18 at 13:59
David TonhoferDavid Tonhofer
5,41513431
5,41513431
6
The general advice is to avoidSwitchbecause, according to its POD... "There are undoubtedly serious bugs lurking somewhere in code this funky"
– toolic
Nov 12 '18 at 14:01
4
The POD on CPAN (metacpan.org/pod/Switch#BUGS) even lists this as a known bug: "On perl 5.10.x may cause syntax error if "case" is present inside heredoc.".
– toolic
Nov 12 '18 at 14:09
4
Switch is a source filter, which means it must parse the Perl code that follows itself. An impossible feat, so it doesn't really actually try. You get errors such as the one you describe, and they can be very hard to debug. Avoid Switch.
– ikegami
Nov 12 '18 at 14:24
add a comment |
6
The general advice is to avoidSwitchbecause, according to its POD... "There are undoubtedly serious bugs lurking somewhere in code this funky"
– toolic
Nov 12 '18 at 14:01
4
The POD on CPAN (metacpan.org/pod/Switch#BUGS) even lists this as a known bug: "On perl 5.10.x may cause syntax error if "case" is present inside heredoc.".
– toolic
Nov 12 '18 at 14:09
4
Switch is a source filter, which means it must parse the Perl code that follows itself. An impossible feat, so it doesn't really actually try. You get errors such as the one you describe, and they can be very hard to debug. Avoid Switch.
– ikegami
Nov 12 '18 at 14:24
6
6
The general advice is to avoid
Switch because, according to its POD... "There are undoubtedly serious bugs lurking somewhere in code this funky"– toolic
Nov 12 '18 at 14:01
The general advice is to avoid
Switch because, according to its POD... "There are undoubtedly serious bugs lurking somewhere in code this funky"– toolic
Nov 12 '18 at 14:01
4
4
The POD on CPAN (metacpan.org/pod/Switch#BUGS) even lists this as a known bug: "On perl 5.10.x may cause syntax error if "case" is present inside heredoc.".
– toolic
Nov 12 '18 at 14:09
The POD on CPAN (metacpan.org/pod/Switch#BUGS) even lists this as a known bug: "On perl 5.10.x may cause syntax error if "case" is present inside heredoc.".
– toolic
Nov 12 '18 at 14:09
4
4
Switch is a source filter, which means it must parse the Perl code that follows itself. An impossible feat, so it doesn't really actually try. You get errors such as the one you describe, and they can be very hard to debug. Avoid Switch.
– ikegami
Nov 12 '18 at 14:24
Switch is a source filter, which means it must parse the Perl code that follows itself. An impossible feat, so it doesn't really actually try. You get errors such as the one you describe, and they can be very hard to debug. Avoid Switch.
– ikegami
Nov 12 '18 at 14:24
add a comment |
1 Answer
1
active
oldest
votes
Don't use Switch if you can possibly avoid it, it's a source filter and you have found one of the bugs lurking in it's depths. given()/when() would be better, but that has problems and is now marked as experimental. If you want the equivalent of a case statement try
for ($test_this)
if ( ! /D/ )
say 'is numbers';
last;
if ( $_ eq 'exit' )
say 'exit found';
last;
if (/^pLu/)
say 'Upper case letter';
last;
# Default option
say 'Default';
last;
answered Nov 12 '18 at 14:15
JGNIJGNI
1,938615
2
Or use a dispatch table if viable.
– simbabque
Nov 12 '18 at 14:33
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
Don't use Switch if you can possibly avoid it, it's a source filter and you have found one of the bugs lurking in it's depths. given()/when() would be better, but that has problems and is now marked as experimental. If you want the equivalent of a case statement try
for ($test_this)
if ( ! /D/ )
say 'is numbers';
last;
if ( $_ eq 'exit' )
say 'exit found';
last;
if (/^pLu/)
say 'Upper case letter';
last;
# Default option
say 'Default';
last;
answered Nov 12 '18 at 14:15
JGNIJGNI
1,938615
2
Or use a dispatch table if viable.
– simbabque
Nov 12 '18 at 14:33
add a comment |
Don't use Switch if you can possibly avoid it, it's a source filter and you have found one of the bugs lurking in it's depths. given()/when() would be better, but that has problems and is now marked as experimental. If you want the equivalent of a case statement try
for ($test_this)
if ( ! /D/ )
say 'is numbers';
last;
if ( $_ eq 'exit' )
say 'exit found';
last;
if (/^pLu/)
say 'Upper case letter';
last;
# Default option
say 'Default';
last;
answered Nov 12 '18 at 14:15
JGNIJGNI
1,938615
2
Or use a dispatch table if viable.
– simbabque
Nov 12 '18 at 14:33
add a comment |
Don't use Switch if you can possibly avoid it, it's a source filter and you have found one of the bugs lurking in it's depths. given()/when() would be better, but that has problems and is now marked as experimental. If you want the equivalent of a case statement try
for ($test_this)
if ( ! /D/ )
say 'is numbers';
last;
if ( $_ eq 'exit' )
say 'exit found';
last;
if (/^pLu/)
say 'Upper case letter';
last;
# Default option
say 'Default';
last;
answered Nov 12 '18 at 14:15
JGNIJGNI
1,938615
Don't use Switch if you can possibly avoid it, it's a source filter and you have found one of the bugs lurking in it's depths. given()/when() would be better, but that has problems and is now marked as experimental. If you want the equivalent of a case statement try
for ($test_this)
if ( ! /D/ )
say 'is numbers';
last;
if ( $_ eq 'exit' )
say 'exit found';
last;
if (/^pLu/)
say 'Upper case letter';
last;
# Default option
say 'Default';
last;
answered Nov 12 '18 at 14:15
JGNIJGNI
1,938615
answered Nov 12 '18 at 14:15
JGNIJGNI
1,938615
answered Nov 12 '18 at 14:15
JGNIJGNI
1,938615
answered Nov 12 '18 at 14:15
JGNIJGNI
1,938615
1,938615
2
Or use a dispatch table if viable.
– simbabque
Nov 12 '18 at 14:33
add a comment |
2
Or use a dispatch table if viable.
– simbabque
Nov 12 '18 at 14:33
2
2
Or use a dispatch table if viable.
– simbabque
Nov 12 '18 at 14:33
Or use a dispatch table if viable.
– simbabque
Nov 12 '18 at 14:33
add a comment |
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6
The general advice is to avoid
Switchbecause, according to its POD... "There are undoubtedly serious bugs lurking somewhere in code this funky"– toolic
Nov 12 '18 at 14:01
4
The POD on CPAN (metacpan.org/pod/Switch#BUGS) even lists this as a known bug: "On perl 5.10.x may cause syntax error if "case" is present inside heredoc.".
– toolic
Nov 12 '18 at 14:09
4
Switch is a source filter, which means it must parse the Perl code that follows itself. An impossible feat, so it doesn't really actually try. You get errors such as the one you describe, and they can be very hard to debug. Avoid Switch.
– ikegami
Nov 12 '18 at 14:24