Regular Expressions 101

Explanation

Pro

^start of line

.any Unicode character (except for line terminators)

Group 1((?!_[vV]\d).)*

*repeats the group contents below any number of times:

Negative Lookahead(?!_[vV]\d)

_the literal _ (95₁₀ / 137₈ / 5F₁₆)

Character Class[vV]

vthe literal v (118₁₀ / 166₈ / 76₁₆) (case sensitive)

Vthe literal V (86₁₀ / 126₈ / 56₁₆) (case sensitive)

\da Unicode decimal digit

.any Unicode character (except for line terminators)

$end of line

Global pattern flags

m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string

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

Detailed match information will be displayed here automatically.

25 tokens

^.((?!_[vV]\d).)*$

something_v0003.nk
something_v003.nk
something_v03.nk
something_v3.nk

# Match file names that don't contain a version number.
something.nk

something_v0003.nk
something_v003.nk
something_v03.nk
something_v3.nk

# Match file names that don't contain a version number.
something.nk