Regular Expressions 101

Explanation

Pro

^start of line

\d+a Unicode decimal digit, repeated at least once

Group 1( *[+=*/-] *\d+)*

*repeats the group contents below any number of times:

*the literal (32₁₀ / 40₈ / 20₁₆) , repeated any number of times

Character Class[+=*/-]

+the literal + (43₁₀ / 53₈ / 2B₁₆)

=the literal = (61₁₀ / 75₈ / 3D₁₆)

*the literal * (42₁₀ / 52₈ / 2A₁₆)

/the literal / (47₁₀ / 57₈ / 2F₁₆)

-the literal - (45₁₀ / 55₈ / 2D₁₆)

*the literal (32₁₀ / 40₈ / 20₁₆) , repeated any number of times

\d+a Unicode decimal digit, 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

Detailed match information will be displayed here automatically.

25 tokens

^\d+( *[+=*/-] *\d+)*$

2+3*4/2
2 + 3
2 + 3 + 2
2+3+2
2+3*4/2+
2 + 3/

2 + 3 + 2-
2+3+2*
2 + 3 * 4 / 2
2 + 3 *4 /2
2
22+32*34/21
22 + 3    2 * 34 /21
22+32*34/
35125125
1-2