I have an array of strings. I want to wrap each string in quotation marks—that is, to prepend and append a quotation mark to each string—unless the string matches a certain pattern. There are many ways to do this, but I want to know why I'm having trouble doing it with map. Here is some example code:

my @strings = qw(boy bird FALSE);
@strings = map { unless (/FALSE/) { "\"$_\"" }} @strings;

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I want this to return

"boy" "bird" FALSE

but it returns

"boy" "bird" 1

and I can't quite figure out why. The 1 appears to come from scalar evaluation of unless (/FALSE/), but why? It seems that $_ is being set to 1 at some point, but I don't see why that should be, either.

In reply to using map with compound code blocks to alter strings: a strange result by jbullock35

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