strict digraph faustflow {
    root=syntax;
    ordering=out;
    
    simple[label="3.1 Simple"];
    fundef[label="3.2 Function"];
    patdef[label="3.3 Pattern"];
    
    diag[label="4.1 Diag."];
    math[label="4.2.1 Math"];
    bit[label="4.2.2 Bitwise"];
    cmp[label="4.2.3 Compare"];
    
    time[label="4.3 Time"];
    env[label="4.4 Lexical"];
    foreign[label="4.5 Foreign"];
    prog[label="4.6 Lambda"];



    node[shape=box, color=blue, fillcolor=lightblue, style=filled];
    syntax[label="1 Program"];
    statement[label="2 Statements"];
    definition[label="3 Definitions"];
    expr[label="4 Expressions"];
    prim[label="5 Primitives"];
    infix[label="4.2 Numericals"];
  

    syntax->statement;
    syntax->definition;
    syntax->expr;
    syntax->prim;
    
    definition->simple;
    definition->fundef;
    definition->patdef;

    expr->diag;		{rank=same; expr simple}
    expr->infix;
    
    infix->math;
    infix->bit;
    infix->cmp;

    expr->time;
    expr->env;
    expr->foreign;
    expr->prog;
    
}