Keywords in Unlang

The following tables list the keywords used in Unlang. These keywords implement the "flow control" of the policies.

Table 1. Flow Control
Keyword	Description
break	Exit early from a `foreach` loop.
case	Match inside of a `switch`.
else	Do something when an `if` does not match.
elsif	Check for condition when a previous `if` does not match.
foreach	Loop over a list of attributes.
if	Check for a condition, and execute a sub-policy if it matches.
return	Immediately stop processing a section.
switch	Check for multiple values.
update	Edit a list of attributes.

The following keywords are also used in unlang. These keywords define policies and groups of policies.

Table 2. Grouping
Keyword	Description
group	Group a series of statements.
load-balance	Define a load balancing group without fail-over.
redundant	Define a redundant group with fail-over.
redundant-load-balance	Define a redundant group with fail-over and load balancing.

The unlang statements can also refer to modules. The modules are pre-packaged libraries that implement specific functionality, such as connecting to SQL, LDAP, etc. The module used here is not the literal string module. Instead, it is the name of a pre-packaged module such as sql, or ldap, or eap.

Table 3. Modules
Keyword	Description
module	Execute a named module, e.g., `sql`.
module.method	Execute a particular method of a named module, e.g., `pap.authorize`
reject	Built-in modules, e.g., `reject`, or `ok`, etc.