how do you re.match to recognize an identifier

[coconutdumplin]

Hi guys

this is my very first python program

I've been trying to use re.match to test to see if a string is an identifier
as defined by this syntax

identifier -> letter{ letter| digit}

I tried the following statements
but when i test my program every single time it gets to a number by its self it still thinks its an identifier which is incorrect..

what am i missing??
your assistance is crucial

Thank you

if re.match("^[\w\d_-]+$", i):
    if re.match("^[A-Za-z0-9_-]*$",i):
    if re.match('\w+(\w\d)+?', i):

[Gribouillis]

Try this

>>> import re
>>> ident_re = re.compile(r"^[a-zA-Z_]\w*$")
>>> ident_re.match("hello")
<_sre.SRE_Match object at 0x7f9b9eac24a8>
>>> ident_re.match("f8888")
<_sre.SRE_Match object at 0x7f9b9eac2510>
>>> ident_re.match("8888")
>>>

Always use strings prefixed with 'r' like in r"..." for regular expressions.

[coconutdumplin]

thanks Gribouillis for responding...
can you tell me what your code means?....
this is my function...i'm unsure exactly how to fit your code in there

def Identifiers(seq,i):
import re
    if re.match(r"^[a-zA-Z_]\w*$",i):

             return True
    else:
            return False

where seq is a string that contains what ever is on each line of a file and i each element in that string

i see where you test to see if its a letter... but what if its something like 1d or dd3 or a3d4....which are all valid identifiers...how would it be able to recognize this..??