Re^4: Warning in objImageMagick

Did this way and it oppressed the warnings:

my $obj_temp = "";
   
   $obj_temp = $objImageMagick->Read("dir/$filename");
  
   warn "$obj_temp" if $obj_temp =~ /(\d+)/; # print the error message
   
   warn "Error Number: ".$1." Number of images read: ".0+$obj_temp if 
+$obj_temp =~ /(\d+)/;
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Comment on Re^4: Warning in objImageMagick Download Code

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Re^5: Warning in objImageMagick by haukex (Archbishop) on Apr 02, 2016 at 17:59 UTC
Hi Anonymous, Actually there's still a bug in there, you'll still get the same "Argument ... isn't numeric in addition" warning when `Read` fails. `warn "message... ".0+$obj_temp` is interpreted by Perl as `warn "message... 0" + $obj_temp;` (i.e. the concatenation happens first) instead of what you want, `warn "message... ".(0+$obj_temp)`. Try it yourself: `perl -MO=Deparse,-p -e 'warn "message... ".0+$obj_temp'` The reason is the operators `+` and `.` have the same precedence but are left associative (compare the output of the aforementioned Deparse with this: `perl -MO=Deparse,-p -e 'warn 0+$obj_temp."message... "'`). You should use parentheses to set the precedence and for clarity. Regards, -- Hauke D	[reply] [d/l] [select]
Re^6: Warning in objImageMagick by Anonymous Monk on Apr 02, 2016 at 18:23 UTC
So this line should be like this: `warn "Error Number: ".$1." Number of images read: ".(0+$obj_temp) if $ +obj_temp =~ /(\d+)/;` [download]	[reply] [d/l]
Re^7: Warning in objImageMagick by haukex (Archbishop) on Apr 02, 2016 at 18:39 UTC
Hi Anonymous, Yes, that's correct. Personally I'd write it with an `if (...) {...}` as I showed in Re^3: Warning in objImageMagick, but since either works, it's up to you. Regards, -- Hauke D	[reply] [d/l]
Re^8: Warning in objImageMagick by Anonymous Monk on Apr 02, 2016 at 19:03 UTC