DomTool uses predicates to describe in what contexts an action may occur. For instance, web-related actions should only occur inside the scope of a virtual host directive. Predicates are built up following the grammar in the table below, using the letter P as the non-terminal for predicates.
Meanings are given as statements that must hold about the context where an action is found. The context is represented as a stack of context IDs which have been declared with context declarations.
Syntax |
Description |
Meaning |
Root |
Root |
The stack is empty. |
CSymbol |
Context ID |
CSymbol is on the top of the stack. |
^P |
Suffixes |
Some (not necessarily strict) suffix of the stack matches P. |
!P |
Not |
The stack doesn't match P. |
P1 & P2 |
And |
The stack matches both P1 and P2. |
(P) |
Grouping |
Identical to P |