O'Reilly logo

Learning AWK Programming by Shiwang Kalkhanda

Stay ahead with the world's most comprehensive technology and business learning platform.

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, tutorials, and more.

Start Free Trial

No credit card required

Grouping using parentheses

This is also known as creating sub-expressions. Single-letter repetition can be easily controlled with unary operators or interval expressions, however, if we need to match the repetition of a word or group of characters, then we have to group that regular expression together inside parentheses. It is quite similar to the grouping of expressions as done in math. Parentheses or grouping is used for two operations, that is, concatenation and back-referencing.

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, interactive tutorials, and more.

Start Free Trial

No credit card required