Regular Expressions 101

Pro

^start of line

\w+any word character, repeated at least once

Non-Capturing Group(?:\[\d+])?

?repeats the group contents below at most once:

\[the literal [ (91₁₀ / 133₈ / 5B₁₆)

\d+a digit, repeated at least once

]the literal ] (93₁₀ / 135₈ / 5D₁₆)

Non-Capturing Group(?:\.\w+(?:\[\d+])?)*

*repeats the group contents below any number of times:

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

\w+any word character, repeated at least once

Non-Capturing Group(?:\[\d+])?

?repeats the group contents below at most once:

\[the literal [ (91₁₀ / 133₈ / 5B₁₆)

\d+a digit, repeated at least once

]the literal ] (93₁₀ / 135₈ / 5D₁₆)

$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.

25 tokens

Regular Expression

^\w+(?:\[\d+])?(?:\.\w+(?:\[\d+])?)*$

New

parent[0].child
parent.child
parent.child1.list[0].child2
parent[500].child
parent0.child
par50ent.child
parent[0].child1[20].child[0]


parent..child
parent[].child
parent[1a].child
parent[a].child
.parent
parent.

Extraction

parent[0].child
parent.child
parent.child1.list[0].child2
parent[500].child
parent0.child
par50ent.child
parent[0].child1[20].child[0]


parent..child
parent[].child
parent[1a].child
parent[a].child
.parent
parent.