Parse Nodes

There are five types of nodes in E-HowNet expression — Entity, Feature, Function, Restriction, and Root.

Major Nodes

class EhnParseNode

The prototype of E-HowNet parsing nodes.

head: str

The head of this node.

children()

Yields all direct child nodes of this node.

descendant()

Yields all descendant nodes (including self) of this node.

tree() → treelib.Tree

Generates a tree representation of this node and all its descendant nodes.

Entity

class EhnParseEntityBase

The base class of E-HowNet parsing entity nodes.

Subclasses:

• EhnParseNormalEntity A normal entity. Can be an anchor.

• EhnParseFunctionEntity An entity with function head. Can be an anchor.

• EhnParseAnyEntity A placeholder entity.

• EhnParseNameEntity A name entity.

• EhnParseNumberEntity A number entity.

• EhnParseTildeEntity An entity refers to the parent entity.

• EhnParseCoindexEntity An entity refers to an anchor entity.

property features

A list of Features.

Feature

class EhnParseFeatureBase

The base class of E-HowNet parsing feature nodes.

Subclasses:

• EhnParseNormalFeature A normal feature.

• EhnParseFunctionFeature An feature with function head.

property value

Can be either Entity or Restriction.

Function

class EhnParseFunctionBase

The base class of E-HowNet parsing function nodes.

Subclasses:

• EhnParseFunction.

property arguments

A list of Entities or Restriction

Restriction

class EhnParseRestrictionBase

The base class of E-HowNet parsing function nodes.

Subclasses:

• EhnParseRestriction. Can be an anchor.

property value

Must be an Entity.

Root

class EhnParseRootBase

The base class of E-HowNet parsing root nodes. Works similar to entities but is not an entity. Used only in feature-based expressions.

Subclasses:

• EhnParseRoot.

property features

A list of Features.

Partial Nodes

Function Head

class EhnParseFunctionHead

The base class of nodes with a function as its head.

Note that the attribute obj.head of this object obj returns obj.function.head.

Subclasses:

• EhnParseFunctionEntity

• EhnParseFunctionFeature

property function

Must be a Function.

Anchor Body

class EhnParseAnchorBody

The base class of anchor nodes.

Subclasses:

• EhnParseNormalEntity

• EhnParseFunctionEntity

• EhnParseRestriction

property anchor

The Anchor.

Anchor

class EhnParseAnchor

The coindex target.

head: str

The coindex of this anchor. Must be x[0-9]*.