Regular Expressions 101

Explanation
Pro

Group 1(^(h([\d]+)\.+?)(.+?)$)

^start of line

Group 2(h([\d]+)\.+?)

hthe literal h (104₁₀ / 150₈ / 68₁₆) (case sensitive)

Group 3([\d]+)

Character Class[\d]+

+matches at least one character from the set below:

\da digit

\.+?the literal . (46₁₀ / 56₈ / 2E₁₆) , repeated at least once

Group 4(.+?)

.+?any character (except for line terminators), repeated at least once

$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

Match Information

Detailed match information will be displayed here automatically.

Quick Reference

25 tokens

Regular Expression

(^(h([\d]+)\.+?)(.+?)$)

New

h1. Topic 1
blah blah blah, because of bla bla bla
h2. PartA
blah blah blah
h3. Part a
blah blah blah
h2. Part B
blah blah blah
h1. Topic 2
and its cuz blah blah
FIN

Substitution

<h$3>$4</h$3>

h1. Topic 1
blah blah blah, because of bla bla bla
h2. PartA
blah blah blah
h3. Part a
blah blah blah
h2. Part B
blah blah blah
h1. Topic 2
and its cuz blah blah
FIN