Advanced usage

By default trrex will use word boundaries "(\b)" to delimit keywords, this could be problematic if the words contain punctuation symbols. You can do the following for those cases:

In [1]: import trrex as tx

In [2]: import re

In [3]: emoticons = [":)", ":D", ":("]

In [4]: pattern = tx.make(emoticons, prefix=r"(?<!\w)", suffix=r"(?!\w)")

In [5]: result = re.findall(pattern, "The smile :), and the laugh :D and the sad :(")

In [6]: result
Out[6]: [':)', ':D', ':(']

In the above example the parenthesis need no escaping because they are inside in a character set:

In [7]: pattern
Out[7]: '(?<!\\w):[D)(](?!\\w)'

In general, however, the regex meta characters need to be escaped in order to match them:

In [8]: words = ["bab.y", "b#ad", "b?at"]

In [9]: pattern = tx.make(map(re.escape, words))

In [10]: pattern
Out[10]: '\\bb(?:ab\\.y|\\(?:?at|#ad))\\b'

Notice that you need to use re.escape for each character of the string in order to work properly with trrex.