Regular Expressions 101

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`
(?i)--.*|/\*(?s).*?\*/
`
gm
1st Alternative
(?i)--.*
(?i)
match the remainder of the pattern with the following effective flags: gmi
i modifier: insensitive. Case insensitive match (ignores case of [a-zA-Z])
--
matches the characters -- literally (case insensitive)
.
matches any character (except for line terminators)
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
2nd Alternative
/\*(?s).*?\*/
/ matches the character / with index 4710 (2F16 or 578) literally (case insensitive)
\* matches the character * with index 4210 (2A16 or 528) literally (case insensitive)
(?s)
match the remainder of the pattern with the following effective flags: gmis
s modifier: single line. Dot matches newline characters
.
matches any character
*? matches the previous token between zero and unlimited times, as few times as possible, expanding as needed (lazy)
\* matches the character * with index 4210 (2A16 or 528) literally (case insensitive)
/ matches the character / with index 4710 (2F16 or 578) literally (case insensitive)
Global pattern flags
g modifier: global. All matches (don't return after first match)
m modifier: multi line. Causes ^ and $ to match the begin/end of each line (not only begin/end of string)
Your regular expression does not match the subject string.

Regular Expression
No Match

`
`
gm

Test String