Regular Expressions 101

Pro

^start of line

Group 1((?:(?:- ?)?\d*\.?\d+|(?:var|perg|ind)?$(?1)$)(?:[-+*\/](?1))*)

Non-Capturing Group(?:(?:- ?)?\d*\.?\d+|(?:var|perg|ind)?$(?1)$)

1st Alternative(?:- ?)?\d*\.?\d+

Non-Capturing Group(?:- ?)?

?repeats the group contents below at most once:

-the literal - (45₁₀ / 55₈ / 2D₁₆)

?optionally matches the literal (32₁₀ / 40₈ / 20₁₆)

\d*a digit, repeated any number of times

\.?optionally matches the literal . (46₁₀ / 56₈ / 2E₁₆)

\d+a digit, repeated at least once

2nd Alternative(?:var|perg|ind)?$(?1)$

Non-Capturing Group(?:var|perg|ind)?

?repeats the group contents below at most once:

1st Alternativevar

varthe literal text var (case sensitive)

2nd Alternativeperg

pergthe literal text perg (case sensitive)

3rd Alternativeind

indthe literal text ind (case sensitive)

\(the literal ( (40₁₀ / 50₈ / 28₁₆)

(?1)calls group 1 as a subroutine

\)the literal ) (41₁₀ / 51₈ / 29₁₆)

Non-Capturing Group(?:[-+*\/](?1))*

*repeats the group contents below any number of times:

Character Class[-+*\/]

-the literal - (45₁₀ / 55₈ / 2D₁₆)

+the literal + (43₁₀ / 53₈ / 2B₁₆)

*the literal * (42₁₀ / 52₈ / 2A₁₆)

\/the literal / (47₁₀ / 57₈ / 2F₁₆)

(?1)calls group 1 as a subroutine

$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+|(?:var|perg|ind)?\((?1)\))(?:[-+*\/](?1))*)$

New

9-8+
(ind(10)+15)-10
(ind(10)+15-10
1000-(perg(25)*2)
1000-perg(25)*2)
1000-perg(25)*2
25/var(1)
12*2-(58+1)/5
(perg(6)*perg(4)*)*1000000
0