Regular Expressions 101

Positive Lookahead(?=\s|\.)

1st Alternative\s

\sany whitespace character

2nd Alternative\.

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

Group 1(\s|.)

1st Alternative\s

\sany whitespace character

2nd Alternative.

.any character (except for line terminators)

Group 2(multi|dual|ita-eng)

1st Alternativemulti

multithe literal text multi (case sensitive)

2nd Alternativedual

dualthe literal text dual (case sensitive)

3rd Alternativeita-eng

ita-engthe literal text ita-eng (case sensitive)

Positive Lookahead(?=\s|\.)

1st Alternative\s

\sany whitespace character

2nd Alternative\.

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

Group 3(\s|.)

1st Alternative\s

\sany whitespace character

2nd Alternative.

.any character (except for line terminators)

Global pattern flags

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

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

Detailed match information will be displayed here automatically.

Search reference

Regular Expression

(?=\s|\.)(\s|.)(multi|dual|ita-eng)(?=\s|\.)(\s|.)

New

ds.multi.
dsd dual
ds.ita-eng.
this is multiplayer 
dualipa
 dual 
.dual.
  dual.
 italian and english
this is aramulti