Hi , i am working with regular expression and got into trouble how to differentiate between two patterns 


LETTER          [A-Za-z]
DIGIT           [0-9]
LABELNAME       {LETTER}(_|{LETTER}|{DIGIT})*

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the above rule of labelname will accept anything. now i want to have another rule 
REGNAME        [pP] 
REG_NUM        [0-9]+

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if i use first one i need to do further coding to get value of reg_num numerical value that why i want to use second one. problem is second rule fits in 1 rule also and so i get error results. is there any way i can have differen rules for second case and just able to have recognized patterns like p0 , P2 from second rule so that i dont need to do extra calculation to extract values as would have been in first case. Thanks

In reply to help related to regular expression by john_costa

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