Regular expression matching [^a-z] or $

Question

I need some help with string regex matching a word in a sentence accounting for punctuation and the end of the line. My attempt fails for the end of line case.

The following examples evaluate as I need:

>>> print bool(re.search('test[^a-z]','test!'.lower()))
True
>>> print bool(re.search('test[^a-z]','test aaa'.lower()))
True
>>> print bool(re.search('test[^a-z]','testaaa'.lower()))
False

However the end of line case evaluates False:

>>> print bool(re.search('test[^a-z]','test'.lower()))
False

The end of line character $ isn't in the set a-z so locigal I thought this case would also evaluate True. How can I handle this in regex?

Answer 1

You can use a negative lookahead:

'test(?![a-z])'

Or an alternation:

'test([^a-z]|$)'