Expressions
An expression is the basic building block of the language. Anything with a value can be thought of as an expression. Examples include:
5 5+5 $a $a==5 sqrt(9)
By combining many of these basic expressions, you can build larger and more complex expressions.
Note that the echo
statement we’ve used in numerous examples
cannot be part of a complex expression because it does not have a
return value. The print
statement, on the other hand, can be used as
part of a complex expression, as it does have a return value. In all
other respects, echo
and print
are identical: they output data.
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