reading-notes

Automation

Readings

Reference

Watchdog

Notes

RegEx

Import from the re library
- import re

Use r"sequence" to define the regex expression

pattern = r"Cookie"
sequence = "Cookie"
if re.match(pattern, sequence):
    print("Match!")
else: print("Not a match!")

search
- With the search function, you scan through the given string/sequence, looking for the first location where the regular expression produces a match
group
- The group function returns the string matched by the re
```
re.search(r'Co.k.e', 'Cookie').group()
# Returns: 'Cookie'
```
- Note: A . will match any single character except the newline character
^ matches the beginning of a string
$ matches the end of a string
[abc] matches a, b, or c
[a-zA-Z0-9] - Matches any letter from (a to z) or (A to Z) or (0 to 9)
\w - Lowercase ‘w’. Matches any single letter, digit, or underscore.
\W - Uppercase ‘W’. Matches any character not part of \w (lowercase w).
\s - Lowercase ‘s’. Matches a single whitespace character like: space, newline, tab, return.
\S - Uppercase ‘S’. Matches any character not part of \s (lowercase s).
\d - Lowercase d. Matches decimal digit 0-9.
\D - Uppercase d. Matches any character that is not a decimal digit.
\t - Lowercase t. Matches tab.
\n - Lowercase n. Matches newline.
\r - Lowercase r. Matches return.
\A - Uppercase a. Matches only at the start of the string. Works across multiple lines as well.
\Z - Uppercase z. Matches only at the end of the string.
\b - Lowercase b. Matches only the beginning or end of the word.
+ - Checks if the preceding character appears one or more times starting from that position.
* - Checks if the preceding character appears zero or more times starting from that position.
? - Checks if the preceding character appears exactly zero or one time starting from that position.
{x} - Repeat exactly x number of times.
{x,} - Repeat at least x times or more.
{x, y} - Repeat at least x times but no more than y times.
{ } - Checks for an explicit number of times.
( ) - Creates a group when performing matches.
< > - Creates a named group when performing matches.