How to check if a string is a valid regex in Python?
PythonRegexStringValidationPython Problem Overview
In Java, I could use the following function to check if a string is a valid regex (source):
boolean isRegex;
try {
Pattern.compile(input);
isRegex = true;
} catch (PatternSyntaxException e) {
isRegex = false;
}
Is there a Python equivalent of the Pattern.compile()
and PatternSyntaxException
? If so, what is it?
Python Solutions
Solution 1 - Python
Similar to Java. Use re.error
exception:
import re
try:
re.compile('[')
is_valid = True
except re.error:
is_valid = False
> exception re.error
>
> Exception raised when a string passed to one of the functions here is
> not a valid regular expression (for example, it might contain
> unmatched parentheses) or when some other error occurs during
> compilation or matching. It is never an error if a string contains no
> match for a pattern.
Solution 2 - Python
Another fancy way to write the same answer:
import re
try:
print(bool(re.compile(input())))
except re.error:
print('False')