![]() ![]() The way the match() method works is that it will only find matches if they occur at the start of the string being searched. Lets first take a look at the match() method. Lets take a look at each of these methods in a little more detail to see how they work and how they differ. The methods that we will be discussing are:Įach of the methods accepts a regular expression, and string to scan for matches. The ‘re’ package provides several methods to actually perform queries on an input string. > rawString = r'and this is a\nraw string'Īnd this is a\nraw string Performing Queries with Regex in Python Essentially, you are telling the parser to completely leave your string alone. When a string is raw, the python parser will not even attempt to make any substitutions within it. ![]() Rather than bend our brains trying to figure out how many backslashes we need, we can instead use raw strings.Ī raw string is created by simply adding an ‘r’ character before the opening quote of a normal string. The combination of these two behaviors would mean that sometimes you would have to escape escape characters themselves (when the special character was recognized by both the python parser and the regex parser), yet other times you would not (if the special character was not recognized by the python parser). This behavior causes a problem when working with regular expressions in python because the ‘re’ package also uses backslash characters to escape special regex characters (like * or ). If the backslash is followed by a special sequence recognized by the parser, the whole escape sequence is replaced by a corresponding special character (for example, ‘\n’ is replaced by a newline character when processed by the parser). The python parser interprets ‘\’ (backslashes) as escape characters in string literals. The package we are interested in using to work with regular expressions in python is appropriately named ‘re’. We’ll then talk about how we can use grouping to work with sub-parts of the matches we found using our queries. We are going to introduce the methods we can use to perform queries over strings in Python. In the first article of this series, we will focus on discussing how we work with regular expressions in python, highlighting python specifics. This article is part of a series of articles on Python Regular Expressions. Python, however, does have some nuances when it come to working with regular expressions. Regular expressions as a concept is not exclusive to Python at all.
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