Regular Expressions 101

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/
-?[0-9]+\.[0-9]{1,20}
/
-
matches the character - with index 4510 (2D16 or 558) literally (case sensitive)
Match a single character present in the list below
[0-9]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
0-9 matches a single character in the range between 0 (index 48) and 9 (index 57) (case sensitive)
\. matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
Match a single character present in the list below
[0-9]
{1,20} matches the previous token between 1 and 20 times, as many times as possible, giving back as needed (greedy)
0-9 matches a single character in the range between 0 (index 48) and 9 (index 57) (case sensitive)

Regular Expression

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/

Unit Tests

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