regex101: JavaScript Match Workspace

Pro

Non-Capturing Group(?:\b[\s]?|[^x])

1st Alternative\b[\s]?

\ban ASCII word boundary

Character Class[\s]?

?matches at most one character from the set below:

\sany whitespace character

2nd Alternative[^x]

Negated Character Class[^x]

xthe literal x (120₁₀ / 170₈ / 78₁₆) (case sensitive)

Group 1([\d]{1}[\d]{2})

Character Class[\d]{1}

{1}matches one character from the set below:

\da digit

Character Class[\d]{2}

{2}matches exactly 2 characters from the set below:

\da digit

Non-Capturing Group(?:[^pi]|[\s]?\b)

1st Alternative[^pi]

Negated Character Class[^pi]

pthe literal p (112₁₀ / 160₈ / 70₁₆) (case sensitive)

ithe literal i (105₁₀ / 151₈ / 69₁₆) (case sensitive)

2nd Alternative[\s]?\b

Character Class[\s]?

?matches at most one character from the set below:

\sany whitespace character

\ban ASCII word boundary

Global pattern flags

g modifier: global. Finds all matches instead of stopping after the first

26 tokens

Regular Expression

(?:\b[\s]?|[^x])([\d]{1}[\d]{2})(?:[^pi]|[\s]?\b)

New

This is (321) an example.
(321) also
including (321) //basically not possible, but can't hurt.
this (321) has another group with a p: 122p
this (321) has another group with a I: 123i
this x235 should be ignored cause (123) is what i want to match.
(123) is what i want, not x111 or 125p or 999i
in this 111 case there is no solution 555
101 202.something

Substitution

This is (321) an example.
(321) also
including (321) //basically not possible, but can't hurt.
this (321) has another group with a p: 122p
this (321) has another group with a I: 123i
this x235 should be ignored cause (123) is what i want to match.
(123) is what i want, not x111 or 125p or 999i
in this 111 case there is no solution 555
101 202.something