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I know I can die but that prints out the script name and line number.

I like to do things like die 'error' if $problem;

Is there a way to do that without printing line number stuff?

It would be nice not to have to use braces if($problem){print 'error';exit}

700 Software
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5 Answers5

24

Adding a newline to the die error message suppresses the added line number/scriptname verbage:

die "Error\n"
runrig
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19

You can append a new line to the die string to prevent perl from adding the line number and file name:

die "oh no!\n" if condition;

Or write a function:

sub bail_out {print @_, "\n"; exit}

bail_out 'oh no!' if condition;

Also keep in mind that die prints to stderr while print defaults to stdout.

Eric Strom
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  • Looks like I will have to write my own function because it will have to write to stdout. (I know that I did not originally state this, but I just realized that the only times I want to avoid the line number is when it prints to stdout). – 700 Software Feb 21 '11 at 20:21
  • @George: you can still use {{die}} – dolmen Feb 24 '11 at 21:53
12

You could use the fairly natural-sounding:

print "I'm going to exit now!\n" and exit if $condition;

If you have perl 5.10 or above and add e.g. use 5.010; to the top of your script, you can also use say, to avoid having to add the newline yourself:

say "I'm going to exit now!" and exit if $condition;
David Precious
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    Note that in the unlikely event that print fails, the program will not exit. Better to say "print(...), exit if $condition;". – Sean Feb 21 '11 at 23:52
  • @Sean note that the parentheses after `print` in that example are required, otherwise it will exit without printing anything. – felwithe Nov 27 '18 at 14:57
1

Here is an answer to the question you completed in you comment to Eric.

To do both (print STDOUT and print without line number) you can still use die by changing the __DIE__ handler:

$SIG{__DIE__} = sub { print @_, "\n"; exit 255 };

die "error" if $problem;
dolmen
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-4

You can create complex messages with sprintf:

die sprintf( ... ) if $problem;
shawnhcorey
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