Not sure it will always work the way you want but you could try to use (?{CODE}) in your regex.

$_ = "glad guy sad gal\n" ;
while( 
    /
        (?{print "$`\n"})
        (\b.a.\b|..l)
        (?{print "\nmatch: $&\n\n"})
    /gx 
){};


__END__
g
gl
gla
glad
glad 
glad g
glad gu
glad guy
glad guy 

match: sad

glad guy sad
glad guy sad 

match: gal
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