USING: assocs kernel namespaces sequences sets ;
IN: graphs
+<PRIVATE
+
: if-graph ( vertex edges graph quot -- )
dupd [ 3drop ] if ; inline
: nest ( key graph -- hash )
[ drop H{ } clone ] cache ; inline
+PRIVATE>
+
: add-vertex ( vertex edges graph -- )
[ [ nest dupd set-at ] curry with each ] if-graph ; inline
swapd [ [ rot ] dip at delete-at drop ] 2curry assoc-each
] if-graph ; inline
+<PRIVATE
+
: (closure) ( obj assoc quot: ( elt -- assoc ) -- )
2over key? [
3drop
[ [ drop ] 3dip (closure) ] 2curry assoc-each
] if ; inline recursive
+PRIVATE>
+
: closure ( obj quot -- assoc )
H{ } clone [ swap (closure) ] keep ; inline