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The iif function implements an immediate "if" clause, returning one of two possible values.

result = iif(condition, trueval, falseval)


condition is the logical condition to test. trueval is the value to return if the condition evaluates to true, falseval if the condition evaluates false.

Return Value

trueval is the condition evaluates true, falseval otherwise.


result = iif("windows"), "is windows", "is not windows")

Note that all expressions are evaluated before the condition is checked; the following expression can not be implemented with an immediate if because it may try to concatenate a string value.

result = iif(x ~= nil, "x is " .. x, "x is nil")