... more complicated than necessary.

Since the decimal digit groups appear to be unambiguously delimited to begin with, no need to worry about a delimiter or capture group at all: 

>perl -wMstrict -le
"$_ = 'ActionLogs.1.22.333.4.5.6.7.8.987.xml';
 ;;
 my @digit_groups = m{ \d+ }xmsg;
 printf qq{'$_' } for @digit_groups;
"
'1' '22' '333' '4' '5' '6' '7' '8' '987'

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In reply to Re^2: RegEx Headaches by AnomalousMonk
in thread RegEx Headaches by oryx3

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