What happens if I have a simple string: my $line = "1elem21elema2a 1 bad13elema2 1 bad elemb2 bad 2 z 1elemc2c13elemc2b13elemb2e13elem2";
That must follow simply rules: Find every alpha character string between the numbers one and two. The string may not include the number one two or three. SO: 1 bad13elema2 = no good, contains 1 and 3 1 bad 1elemb2 = no good, contains space 13elema2 = no good, contains 3 ???