Graphviz: specify style of nodes using inline notation

Question

I have a graph looking like:

digraph R {
  rankdir=LR
  "foo" -> "bar";
}

Now I want that the node style of foo is a square and bar is a circle. Also, in subsequent uses, this should be the case, e.g.:

digraph R {
  rankdir=LR
  "foo" -> "bar" [label="qux1"];
  "baz" -> "foo" [label="qux2"];
}

Then foo should be a square. Is there a way to specify this using this inline documentation?

Note! I know that I can write:

digraph G {
  { 
    node1 [shape=box, label="foo"]
    node2 [shape=circle, label="bar"]
    node1 -> node2 [label="qux"]
  }
}

but this is not what I want. I want to use this specific inline notation.

Answer 1

As stated above, the dot language grammar does not support this. A workaround can be done by using subgraphs:

digraph G {
   subgraph { nodefoo [label="foo", shape=box]; } ->  
   subgraph { nodebar [label="bar", shape=circle]; } 
   [label="qux"];
}

Answer 2

What you are asking for is not possible - unfortunately, there is no other answer.

If you take a look at the grammar of the dot language:

graph       :   [ strict ] (graph | digraph) [ ID ] '{' stmt_list '}'
stmt_list   :   [ stmt [ ';' ] stmt_list ]
stmt        :   node_stmt
            |   edge_stmt
            |   attr_stmt
            |   ID '=' ID
            |   subgraph
attr_stmt   :   (graph | node | edge) attr_list
attr_list   :   '[' [ a_list ] ']' [ attr_list ]
a_list      :   ID '=' ID [ (';' | ',') ] [ a_list ]
edge_stmt   :   (node_id | subgraph) edgeRHS [ attr_list ]
edgeRHS     :   edgeop (node_id | subgraph) [ edgeRHS ]
node_stmt   :   node_id [ attr_list ]
node_id     :   ID [ port ]
port        :   ':' ID [ ':' compass_pt ]
            |   ':' compass_pt
subgraph    :   [ subgraph [ ID ] ] '{' stmt_list '}'
compass_pt  :   (n | ne | e | se | s | sw | w | nw | c | _)

The composition of the edge_stmt does not contain node attributes. The only statement allowing node attributes is the node_stmt.