Iterate through an array starting at a given offset, execute a filter expression against each element, and create a new member with references to the members in the output array. See also miva_array_filter.
miva_array_filter_ref( array var, offset, element var, filter_expression, output var )
Return value: Count of output array elements.
array var = Source array of structures.
offset = index in the array to start filtering from.
element var = Name of a variable to reference in the filter expression.
filter_expression = Text of an expression to execute based on the individual array element.
output var = Output array of all structures that tested true in the filter expression.
In this example the array l.facets is filtered into a new array l.enabled_facets
by reference. Reference means that l.enabled_facets does not contain a copy of
the filtered records, but a pointer to the original record, this is faster and
uses less memory than miva_array_filter( )