Regular Expressions 101

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`
^\s{1,}|\s{1,}$
`
g
1st Alternative
^\s{1,}
^ asserts position at start of the string
\s
matches any whitespace character (equivalent to [\r\n\t\f\v ])
{1,} matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
2nd Alternative
\s{1,}$
\s
matches any whitespace character (equivalent to [\r\n\t\f\v ])
{1,} matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
$ asserts position at the end of the string
Global pattern flags
g modifier: global. All matches (don't return after first match)
Your regular expression does not match the subject string.

Regular Expression
No Match

`
`
g

Test String