1. A computer-implemented method for controlling access to structured documents, the method comprising: providing an access control policy for a structured document comprising a plurality of nodes, wherein the access control policy comprises a plurality of access control rules; generating a path for each of the plurality of nodes in the structured document; and generating an executable value expression for each path by normalizing the plurality of access control rules into a format comprising a head, a path, and a condition that indicates who is granted or denied access to each path, generating and populating a condition table to convert the plurality of normalized access control rules into a plurality of modified normalized access control rules, propagating the plurality of modified normalized access control rules for each generated path to identify at least one generated path that is affected by at least one of the plurality of modified normalized access control rules, combining at least two modified normalized access control rules of the plurality of modified normalized access control rules if the at least two modified normalized access control rules affect a particular generated path, optimizing the plurality of modified normalized access control rules by eliminating repeated value expressions, and transforming the plurality of modified normalized access control rules into the executable value expression for each path based on the condition, wherein the executable value expression is utilized during access control evaluation to determine whether a user is allowed to access at least one of the plurality of nodes in the structured document.