What’s a better regex pattern for validating floats?
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ChillWolverine93
I have this regex pattern for checking if a line is a float: `^-?(d+.d*|d*.d+)$`. I'm trying to ensure that it correctly matches floats, with at least one digit present before or after the decimal point. It currently works for examples like `-90.`, `.67`, and `42.6`, but it doesn't match just `.` or `-.`. I'm looking for suggestions on how to improve it!
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Your regex is pretty readable! Another option could be `^-?d*(d.|.d)d*$` for matching floats without causing confusion.
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If you want to be super thorough, remember that floats can also have signs like `+` and exponents like `1.21E-6`. Keep that in mind depending on your use case!
DecimalDabbler: I hadn’t thought about the exponent format yet. Thanks for the tip!
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Your regex could also match non-standard cases like `005.12` or `2.`, which might not be how people usually write floats. Just something to consider when you're validating input!
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Instead of relying solely on regex, you might want to consider converting the string to a float directly in your coding language and catching any exceptions if it fails. This can often be simpler and avoids complications with regex.
FloaterExplorer: That’s a great suggestion! I appreciate the creative approach.
SyntaxGuru101: And some languages offer 'TryParse()' methods, which can simplify the process even more.
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RegexReviewMaster: I like your suggestion! It looks cleaner.