digraph {

node [fontname="Hack", shape=box];

edge [fontname="Hack", fontsize=12];

ranksep=1;

{ rank=same;

node [fontsize=18, style=filled, fillcolor=lightblue];

E; T; "()";

}

{ rank=same;

node [style=rounded, fontsize=12];

Err [label="Err(e)"];

None;

Ok [label="Ok(t)"];

Some [label="Some(t)"];

unwrap_expect [label=<<font color="red">unwrap, expect,</font><br/>unwrap_or[_else],<br/>unwrap_or_default>];

unwrap_err [label="unwrap_err,\nexpect_err", fontcolor=red];

unwrap_none [label="unwrap_none,\nexpect_none", fontcolor=red];

}

{ rank=same;

or [label="or[_else]", style=rounded, fontsize=12];

"Result<T, E>" [fontsize=24, style=filled, fillcolor=lightblue];

"Option<T>" [fontsize=24, style=filled, fillcolor=lightblue];

filter [label="filter, xor,\nor[_else],\nreplace", style=rounded, fontsize=12];

}

{ rank=same;

node [style=rounded, fontsize=12];

err;

map1 [label="map,\nand[_then]"];

map2 [label="map,\nand[_then]"];

map_err;

map_or [label="map_or[_else]"];

}

{ rank=same;

node [fontsize=18, style=filled, fillcolor=lightblue];

U; "Result<T, F>"; "Result<U, E>"; "Option<U>"; "Option<E>";

}

Err -> or [style=invis]; // force "or" to the left of "Result"

map1 -> map_or [style=invis];

{

"Result<T, E>" -> or -> "Result<T, E>";

"Result<T, E>" -> "Option<T>" [label="ok"];

"Result<T, E>" -> err -> "Option<E>";

"Result<T, E>" -> unwrap_err -> E;

"Result<T, E>" -> unwrap_expect -> T;

"Result<T, E>" -> map_or -> U;

"Result<T, E>" -> map_err -> "Result<T, F>";

"Result<T, E>" -> map1 -> "Result<U, E>";

"Option<T>" -> filter -> "Option<T>";

"Option<T>" -> "Result<T, E>" [label="ok_or[_else]"];

"Option<T>" -> unwrap_expect;

"Option<T>" -> unwrap_none -> "()";

"Option<T>" -> map2 -> "Option<U>";

"Option<T>" -> map_or;

E -> Err -> "Result<T, E>";

T -> Ok -> "Result<T, E>";

T -> Some -> "Option<T>";

"()" -> None -> "Option<T>";

}

}