This one has me puzzled.

This works: 

s{  ( [a-zA-Z]+ (?: ' [a-zA-Z]{1,2} )? )  }{

    exists $dict{ lc( $1 ) } ? $1 : "<@>$1";

    }exg;

[download]

And this works: 

s{  ( [a-zA-Z]+ (?: ' [a-zA-Z]{1,2} )? )  }{

    my $x = $1;
 
    exists $dict{ lc( $x ) } ? $1 : "<@>$1";

    }exg;

[download]

But this: 

s{  ( [a-zA-Z]+ (?: ' [a-zA-Z]{1,2} )? )  }{

    my $x = $1;
 
    $x =~ s/'s\z//;

    exists $dict{ lc( $x ) } ? $1 : "<@>$1";

    }exg;

[download]

Produces the message: 

Use of uninitialized value in substitution iterator at ...

[download]

Any ideas why this is happening?

Naked blocks are fun! -- Randal L. Schwartz, Perl hacker

In reply to Use of uninitialized value message? by jwkrahn

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