Here is a list of all documented namespace enum values with links to the namespaces they belong to:

INLINE : srchilite
ISBOLD : srchilite
ISFIXED : srchilite
ISITALIC : srchilite
ISNOREF : srchilite
ISNOTFIXED : srchilite
ISUNDERLINE : srchilite
POSTDOC : srchilite
POSTLINE : srchilite