Module ast

Expand description

AST types for representing parsed GraphQL documents.

This AST structure provides a zero-copy AST for GraphQL documents. All node types are parameterized over a 'src lifetime that borrows strings (whenever possible) from the source text via Cow<'src, str>.

Each AST node has two conceptual layers:

Semantic layer (always present): Typed structs with names, values, directives, and all GraphQL semantics.
Syntax layer (optional): Each node has an Option<XyzSyntax<'src>> field that, when populated, contains keyword/punctuation tokens with their trivia (whitespace, comments, commas). This enables lossless source reconstruction for formatter and IDE tooling.

§Example

use libgraphql_parser::ast;
use libgraphql_parser::GraphQLParser;

// Parse a string into an AST
let parser = GraphQLParser::new("type Query { hello: String }");
let result = parser.parse_schema_document();

// Extract the `Query` type definition
let doc: &ast::Document<'_> = result.valid().unwrap().0;
let query_def = match &doc.definitions[0] {
    ast::Definition::TypeDefinition(
        ast::TypeDefinition::Object(obj),
    ) => obj,
    _ => panic!("expected an object type definition"),
};

// Count the number of fields on the `Query` object
let num_query_fields = query_def.fields.len();
println!("The `Query` object has {num_query_fields} fields.");

Structs§

Argument: A single argument in a field selection or directive annotation.
ArgumentSyntax: Syntax detail for an Argument.
BooleanValue: A GraphQL boolean value (true or false).
BooleanValueSyntax: Syntax detail for a BooleanValue.
DelimiterPair: A matched pair of delimiter tokens (parentheses, brackets, or braces). Bundled into one struct so that an open delimiter without a matching close is unrepresentable.
DirectiveAnnotation: A directive annotation applied to a definition or field (e.g. @deprecated(reason: "Use newField")).
DirectiveAnnotationSyntax: Syntax detail for a DirectiveAnnotation.
DirectiveDefinition: A directive definition.
DirectiveDefinitionSyntax: Syntax detail for a DirectiveDefinition.
DirectiveLocation: A directive location with its own span (unlike graphql_parser which uses a plain enum).
DirectiveLocationSyntax: Syntax detail for a DirectiveLocation.
Document: Root AST node for any GraphQL document.
DocumentSyntax: Syntax detail for a Document.
EnumTypeDefinition: An enum type definition.
EnumTypeDefinitionSyntax: Syntax detail for an EnumTypeDefinition.
EnumTypeExtension: An enum type extension.
EnumTypeExtensionSyntax: Syntax detail for an EnumTypeExtension.
EnumValue: A GraphQL enum value (an unquoted name that is not true, false, or null).
EnumValueDefinition: An enum value definition within an enum type.
EnumValueSyntax: Syntax detail for an EnumValue (the enum value literal, not the enum value definition).
FieldDefinition: A field definition within an object type or interface type.
FieldDefinitionSyntax: Syntax detail for a FieldDefinition.
FieldSelection: A field selection within a selection set, optionally aliased, with arguments, directives, and a nested selection set.
FieldSelectionSyntax: Syntax detail for a FieldSelection.
FloatValue: A GraphQL float value.
FloatValueSyntax: Syntax detail for a FloatValue.
FragmentDefinition: A named fragment definition.
FragmentDefinitionSyntax: Syntax detail for a FragmentDefinition.
FragmentSpread: A named fragment spread (...FragmentName).
FragmentSpreadSyntax: Syntax detail for a FragmentSpread.
InlineFragment: An inline fragment (... on Type { ... } or ... { ... }).
InlineFragmentSyntax: Syntax detail for an InlineFragment.
InputObjectTypeDefinition: An input object type definition.
InputObjectTypeDefinitionSyntax: Syntax detail for an InputObjectTypeDefinition.
InputObjectTypeExtension: An input object type extension.
InputObjectTypeExtensionSyntax: Syntax detail for an InputObjectTypeExtension.
InputValueDefinition: An input value definition, used for field arguments and input object fields.
InputValueDefinitionSyntax: Syntax detail for an InputValueDefinition.
IntValue: A GraphQL integer value.
IntValueSyntax: Syntax detail for an IntValue.
InterfaceTypeDefinition: An interface type definition.
InterfaceTypeDefinitionSyntax: Syntax detail for an InterfaceTypeDefinition.
InterfaceTypeExtension: An interface type extension.
InterfaceTypeExtensionSyntax: Syntax detail for an InterfaceTypeExtension.
ListTypeAnnotation: A list type reference (e.g. [String], [String!]!).
ListTypeAnnotationSyntax: Syntax detail for a ListTypeAnnotation.
ListValue: A GraphQL list value (e.g., [1, 2, 3]).
ListValueSyntax: Syntax detail for a ListValue.
Name: A GraphQL name (identifier).
NameSyntax: Syntax detail for a Name.
NamedTypeAnnotation: A named type reference (e.g. String, String!).
NullValue: A GraphQL null literal.
NullValueSyntax: Syntax detail for a NullValue.
ObjectField: A single field within a GraphQL input object value.
ObjectFieldSyntax: Syntax detail for an ObjectField.
ObjectTypeDefinition: An object type definition.
ObjectTypeDefinitionSyntax: Syntax detail for an ObjectTypeDefinition.
ObjectTypeExtension: An object type extension.
ObjectTypeExtensionSyntax: Syntax detail for an ObjectTypeExtension.
ObjectValue: A GraphQL input object value (e.g., {x: 1, y: 2}).
ObjectValueSyntax: Syntax detail for an ObjectValue.
OperationDefinition: An operation definition (query, mutation, or subscription).
OperationDefinitionSyntax: Syntax detail for an OperationDefinition.
RootOperationTypeDefinition: A root operation type definition within a schema definition (e.g. query: Query).
RootOperationTypeDefinitionSyntax: Syntax detail for a RootOperationTypeDefinition.
ScalarTypeDefinition: A scalar type definition (e.g. scalar DateTime).
ScalarTypeDefinitionSyntax: Syntax detail for a ScalarTypeDefinition.
ScalarTypeExtension: A scalar type extension.
ScalarTypeExtensionSyntax: Syntax detail for a ScalarTypeExtension.
SchemaDefinition: A GraphQL schema definition.
SchemaDefinitionSyntax: Syntax detail for a SchemaDefinition.
SchemaExtension: A schema extension.
SchemaExtensionSyntax: Syntax detail for a SchemaExtension.
SelectionSet: A selection set — the set of fields and fragments selected within braces { ... }.
SelectionSetSyntax: Syntax detail for a SelectionSet.
StringValue: A GraphQL string value.
StringValueSyntax: Syntax detail for a StringValue.
TypeCondition: A type condition (e.g., on User) used in fragment definitions and inline fragments.
TypeConditionSyntax: Syntax detail for a TypeCondition.
UnionTypeDefinition: A union type definition.
UnionTypeDefinitionSyntax: Syntax detail for a UnionTypeDefinition.
UnionTypeExtension: A union type extension.
UnionTypeExtensionSyntax: Syntax detail for a UnionTypeExtension.
VariableDefinition: A variable definition within an operation’s variable list (e.g. $id: ID! = "default").
VariableDefinitionSyntax: Syntax detail for a VariableDefinition.
VariableReference: A variable reference in a GraphQL value position (e.g., $id).
VariableReferenceSyntax: Syntax detail for a VariableReference.

Enums§

Definition: A top-level definition in a GraphQL document.
DefinitionKind: The kind of definition found in a GraphQL document.
DirectiveLocationKind: The kind of location where a directive may be applied.
DocumentKind: The kind of GraphQL document being parsed.
Nullability: The nullability of a type reference.
OperationKind: The kind of a GraphQL operation.
Selection: A single selection within a selection set.
TypeAnnotation: A GraphQL type reference (type annotation).
TypeDefinition: A type definition in a GraphQL schema.
TypeExtension: A type extension in a GraphQL schema.
Value: A GraphQL input value.

Traits§

AstNode: Trait implemented by all AST node types. Provides source reconstruction and span access methods.

Module ast

Module ast Copy item path

§Example

Structs§

Enums§

Traits§

Module ast