Enum NodeShape 

pub enum NodeShape {
    Rectangle,
    Rounded,
    Diamond,
    Circle,
    Stadium,
    Subroutine,
    Cylinder,
    Hexagon,
    Asymmetric,
    Parallelogram,
    Trapezoid,
    ParallelogramBackslash,
    TrapezoidInverted,
    DoubleCircle,
    Bar(BarOrientation),
    Note,
}

The visual shape used to render a node.

Variants

Rectangle

Square corners: ┌──┐ │ │ └──┘

Rounded

Rounded corners: ╭──╮ │ │ ╰──╯

Diamond

Diamond / decision box rendered with / and \ corners.

Circle

Circle rendered as a rounded box with parenthesis markers.

Stadium

Stadium / pill: rounded box with ( / ) markers at vertical midpoints.

Mermaid syntax: ([label])

Subroutine

Subroutine: rectangle with an extra inner vertical bar on each side.

Mermaid syntax: [[label]]

Cylinder

Cylinder (database): rectangle with arc markers at top and bottom centres.

Mermaid syntax: [(label)]

Hexagon

Hexagon: rectangle with < / > markers at vertical midpoints of left/right edges.

Mermaid syntax: {{label}}

Asymmetric

Asymmetric flag: rectangle with a ⟩ marker at the right vertical midpoint.

Mermaid syntax: >label]

Parallelogram

Parallelogram (lean-right): rectangle with / markers at top-left / bottom-right corners.

Mermaid syntax: [/label/]

Trapezoid

Trapezoid (wider top): rectangle with / at top-left and \ at top-right corners.

Mermaid syntax: [/label\]

ParallelogramBackslash

Parallelogram leaning left (backslash variant): rectangle with \ markers at top-left and bottom-right corners.

Mermaid syntax: [\label\]

TrapezoidInverted

Inverted trapezoid (wider bottom): rectangle with \ at top-left and / at top-right corners, indicating a narrower top.

Mermaid syntax: [\label/]

DoubleCircle

Double circle: two concentric rounded boxes, one cell inside the other.

Mermaid syntax: (((label)))

Bar(BarOrientation)

UML synchronisation bar — a single line used as a fork (one incoming, many outgoing) or join (many incoming, one outgoing) point in parallel-flow state machines.

The orientation is perpendicular to the flow direction (so edges fan in/out across its long axis):

• In LR/RL flow: BarOrientation::Vertical — a column of ┃ glyphs.
• In TD/BT flow: BarOrientation::Horizontal — a row of ━ glyphs.

Fork and join are visually identical (only the semantic role differs); both use this single shape variant. The renderer skips drawing the node label for Bar(_) shapes — bars are connection points, not labelled states.

Mermaid syntax: state X <<fork>> / state X <<join>> (and the [[…]] alternative spellings).

Note

State-diagram note (Mermaid note left|right|over of …). Synthesised at parse time as a regular Node with this shape and connected to its anchor via an EdgeStyle::Dotted / EdgeEndpoint::None edge. Renders as a small rounded box — the dotted connector visually distinguishes it from regular rounded states without needing a separate dashed-border primitive (a future variant could add one).

Trait Implementations

impl Clone for NodeShape

fn clone(&self) -> NodeShape

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for NodeShape

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for NodeShape

fn default() -> NodeShape

Returns the “default value” for a type.

impl PartialEq for NodeShape

fn eq(&self, other: &NodeShape) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for NodeShape

impl Eq for NodeShape

impl StructuralPartialEq for NodeShape