Properties of non-properties in the containing loops can be
accessed by immediately following the property statement with a level number and
a semicolon:
The level number can be used as a suffix on many other
commands that output information about the current element, e.g.
id. If no level number is specified the
default is 0, the current loop. Note that outside of all the loops the current
element is the element (normally a graph) the generator is being run on.
Negative level numbers can also be used: –1 is the element (normally a
graph) the generator is being run on, –2 the element of the outermost
loop, etc. In generators in symbols, the stack is pre-loaded with the graph and
the element whose symbol is being displayed. In identifier
generators
, the stack is pre-loaded with the element
whose identifier is being
generated.