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How do I test for a blank line when reading from a file?

( #36246=categorized question: print w/ replies, xml ) Need Help??
Contributed by bravismore on Oct 11, 2000 at 20:50 UTC
Q&A  > files


Answer: How do I test for a blank line when reading from a file?
contributed by merlyn

print "it's blank" unless /\S/;
(This assumes that a line consisting of only whitespace characters is considered blank.)
Answer: How do I test for a blank line when reading from a file?
contributed by thanos1983

Extending runrig's answer to cover the case where "blank" could include whitespace characters (as merlyn's answer already does, negatively): Use /^\s*$/
As in:

while (<>) { print "blank line detected\n" if /^\s*$/; }

Answer: How do I test for a blank line when reading from a file?
contributed by runrig

If by "blank" you mean "empty", then /^$/, as in:

while (<>) { print "blank line detected\n" if /^$/; }

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