I'm trying to play with the sample code for lookahead assertions in Mastering Regular Expressions. On pg. 230 neither of the regexes given for what looks to be matching integers works in all cases. 
my $numbers="1 1.0 3.547 92.34 343.2234";
while($numbers=~/(\d+)(?![\d.])/g){
   print "$1 is an integer\n";
}
print "-"x20,"\n";
while($numbers=~/(\d+)(?=[^.\d])/g){
   print "$1 is an integer\n";
}

[download]
Results: 
1 is an integer
0 is an integer
547 is an integer
34 is an integer
2234 is an integer
--------------------
1 is an integer
0 is an integer
547 is an integer
34 is an integer

Clearly I don't want to capture things that follow a decimal point. I tried prepending (^|[^.\d]) The front of each of these yet it didn't seem to help only made the results even more bizarre. Any suggestions?

In reply to How can I match all the integers in a string? by Anonymous Monk

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