Regular Expressions 101

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/
http(?:s)?\://boards\.4chan\.org/([a-z]*)/thread/([0-9]*)(?:\#[0-9a-z]*)?
/
g
All the errors detected are listed below, from left to right, as they appear in the pattern.
/ An unescaped delimiter must be escaped with a backslash (\)
/ An unescaped delimiter must be escaped with a backslash (\)
/ An unescaped delimiter must be escaped with a backslash (\)
/ An unescaped delimiter must be escaped with a backslash (\)
/ An unescaped delimiter must be escaped with a backslash (\)
Your regular expression does not match the subject string.

Regular Expression
No Match

/
/
g

Test String

Substitution

Processing...