That depends on what you mean by 'pure numbers'. 87? 99.00? 0.5? Let's assume all of that are numbers...
Is there a way to a create a regular expression character class that has some mandatory and optional members?
Yes, but you should probably use the function "looks_like_number" from Scalar::Util
What would be your way to match (not necessarily replace) these "words"?
use 5.020;
use warnings;
# for umlauts and stuff... not really necessary
# but a good idea regardless
use utf8;
use open qw{ :encoding(utf-8) :std };
use Scalar::Util 'looks_like_number';
my $string1 = 'foo 1foo; foo_2 foo-bar() 87 - _ !@#$% ';
my $string2 = 'F? 1_1 99.00 .5 \\x87 14 fourteen !@#99$% 000';
my $test_string = $string1 . $string2;
while ( $test_string =~ m/ (\S+) /gx ) { # or whatever is a "word"
my ( $word, $start, $end ) = ( $1, $-[0], $+[0] );
next if $word !~ m/ \d+ /x or looks_like_number($word);
say qq{"$word" has numbers, but doesn't look like number. Start: $
+start, end: $end};
}
Output:
"1foo;" has numbers, but doesn't look like number. Start: 4, end: 9
"foo_2" has numbers, but doesn't look like number. Start: 12, end: 17
"1_1" has numbers, but doesn't look like number. Start: 48, end: 51
"\x87" has numbers, but doesn't look like number. Start: 61, end: 65
"!@#99$%" has numbers, but doesn't look like number. Start: 78, end: 8
+5
Further down the road the actual task is to find the position of the next "word".
The positions are stored in magic arrays @- and @+
@LAST_MATCH_START
@-
$-[0] is the offset of the start of the last successful match
...
@LAST_MATCH_END
@+
This array holds the offsets of the ends of the last
successful submatches in the currently active dynamic scope.
