Name
$=
Synopsis
When trying to match tokens in the workspace to members of a class,
you can use the $= operator. For example, consider
the following rule:
R $+ < @ $={InternalHosts} > $: $1 < @ mailhub >Here, the workspace is expected to hold a focused address (such as
gw<@wash.dc.gov>). The
$={InternalHosts} expression causes
sendmail to look up the host part of the address
(the wash.dc.gov) in the class
{InternalHosts}. If that host is found in that
class, a match is made and the workspace is rewritten by the RHS to
become gw<@mailhub>.
Class macros in general are described in Chapter 22, and the $= operator in
particular is described in full in Section 22.2.1.
Note that the $= operator can be used only on the
LHS of rules, and that the $= operator can be
referenced by an RHS
$digit operator.
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