Regular Expressions 101

^start of line

Group 1([a-z]+)

Character Class[a-z]+

+matches at least one character from the set below:

a-zone character from a (97₁₀) to z (122₁₀) (case sensitive)

-the literal - (45₁₀ / 55₈ / 2D₁₆)

Group 2((?:(?:0|[1-9](?:[0-9]+)?)\.){2}(?:0|[1-9](?:[0-9]+)?))

Non-Capturing Group(?:(?:0|[1-9](?:[0-9]+)?)\.){2}

{2}repeats the group contents below exactly 2 times:

Non-Capturing Group(?:0|[1-9](?:[0-9]+)?)

1st Alternative0

0the literal 0 (48₁₀ / 60₈ / 30₁₆)

2nd Alternative[1-9](?:[0-9]+)?

Character Class[1-9]

1-9one character from 1 (49₁₀) to 9 (57₁₀)

Non-Capturing Group(?:[0-9]+)?

?repeats the group contents below at most once:

Character Class[0-9]+

+matches at least one character from the set below:

0-9one character from 0 (48₁₀) to 9 (57₁₀)

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

Non-Capturing Group(?:0|[1-9](?:[0-9]+)?)

1st Alternative0

0the literal 0 (48₁₀ / 60₈ / 30₁₆)

2nd Alternative[1-9](?:[0-9]+)?

Character Class[1-9]

1-9one character from 1 (49₁₀) to 9 (57₁₀)

Non-Capturing Group(?:[0-9]+)?

?repeats the group contents below at most once:

Character Class[0-9]+

+matches at least one character from the set below:

0-9one character from 0 (48₁₀) to 9 (57₁₀)

$end of line

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

^([a-z]+)-((?:(?:0|[1-9](?:[0-9]+)?)\.){2}(?:0|[1-9](?:[0-9]+)?))$

New

package-0.0.1
package-0.1.1
package-1.0.1
package-0.10.1
package-0.01.1
package-01.0.1
package-0.0.01