File: gawk.info,  Node: Expressions,  Next: Patterns and Actions,  Prev: Printing,  Up: Top

6 Expressions
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Expressions are the basic building blocks of 'awk' patterns and actions.
An expression evaluates to a value that you can print, test, or pass to
a function.  Additionally, an expression can assign a new value to a
variable or a field by using an assignment operator.

   An expression can serve as a pattern or action statement on its own.
Most other kinds of statements contain one or more expressions that
specify the data on which to operate.  As in other languages,
expressions in 'awk' can include variables, array references, constants,
and function calls, as well as combinations of these with various
operators.

* Menu:

* Values::                      Constants, Variables, and Regular Expressions.
* All Operators::               'gawk''s operators.
* Truth Values and Conditions:: Testing for true and false.
* Function Calls::              A function call is an expression.
* Precedence::                  How various operators nest.
* Locales::                     How the locale affects things.
* Expressions Summary::         Expressions summary.