On 3/7/11 11:48 PM, Peggy Russell wrote:
> It would be helpful if indirection was explained in the documentation for
> [[ expression ]], [ expression ], and declare.
The existing documentation seems pretty clear:
Shell variables are allowed as operands; parameter expansion is per-
formed before the expression is evaluated. Within an expression, shell
variables may also be referenced by name without using the parameter
expansion syntax. A shell variable that is null or unset evaluates to
0 when referenced by name without using the parameter expansion syntax.
The value of a variable is evaluated as an arithmetic expression when
it is referenced, or when a variable which has been given the integer
attribute using declare -i is assigned a value. A null value evaluates
to 0. A shell variable need not have its integer attribute turned on
to be used in an expression.
--
``The lyf so short, the craft so long to lerne.'' - Chaucer
``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, ITS, CWRU [email protected] http://cnswww.cns.cwru.edu/~chet/
