ast

package
v0.0.4-rc1 Latest Latest
Warning

This package is not in the latest version of its module.

 Go to latest Published: Jul 1, 2019 License: Apache-2.0 Imports: 4 Imported by: 161

Documentation

Overview

Package ast declares the types used to represent syntax trees for CUE packages.

Index

Constants

This section is empty.

Variables

This section is empty.

Functions

func LabelName 

func LabelName(x Label) (name string, ok bool)

LabelName reports the name of a label, if known, and whether it is valid.

func Walk 

func Walk(node Node, before func(Node) bool, after func(Node))

Walk traverses an AST in depth-first order: It starts by calling f(node); node must not be nil. If before returns true, Walk invokes f recursively for each of the non-nil children of node, followed by a call of after. Both functions may be nil. If before is nil, it is assumed to always return true.

Types

type Alias 

type Alias struct {
	Ident *Ident    // field name, always an Ident
	Equal token.Pos // position of "="
	Expr  Expr      // An Ident or SelectorExpr
	// contains filtered or unexported fields
}

An Alias binds another field to the alias name in the current struct.

func (*Alias) AddComment 

func (c *Alias) AddComment(cg *CommentGroup)

func (*Alias) Comments 

func (c *Alias) Comments() []*CommentGroup

func (*Alias) End 

func (a *Alias) End() token.Pos

func (*Alias) Pos 

func (a *Alias) Pos() token.Pos

type Attribute 

type Attribute struct {
	At   token.Pos
	Text string // must be a valid attribute format.
	// contains filtered or unexported fields
}

An Attribute provides meta data about a field.

func (*Attribute) AddComment 

func (c *Attribute) AddComment(cg *CommentGroup)

func (*Attribute) Comments 

func (c *Attribute) Comments() []*CommentGroup

func (*Attribute) End 

func (a *Attribute) End() token.Pos

func (*Attribute) Pos 

func (a *Attribute) Pos() token.Pos

type BadDecl 

type BadDecl struct {
	From, To token.Pos // position range of bad declaration
	// contains filtered or unexported fields
}

A BadDecl node is a placeholder for declarations containing syntax errors for which no correct declaration nodes can be created.

func (*BadDecl) AddComment 

func (c *BadDecl) AddComment(cg *CommentGroup)

func (*BadDecl) Comments 

func (c *BadDecl) Comments() []*CommentGroup

func (*BadDecl) End 

func (d *BadDecl) End() token.Pos

func (*BadDecl) Pos 

func (d *BadDecl) Pos() token.Pos

type BadExpr 

type BadExpr struct {
	From, To token.Pos // position range of bad expression
	// contains filtered or unexported fields
}

A BadExpr node is a placeholder for expressions containing syntax errors for which no correct expression nodes can be created. This is different from an ErrorExpr which represents an explicitly marked error in the source.

func (*BadExpr) AddComment 

func (c *BadExpr) AddComment(cg *CommentGroup)

func (*BadExpr) Comments 

func (c *BadExpr) Comments() []*CommentGroup

func (*BadExpr) End 

func (x *BadExpr) End() token.Pos

func (*BadExpr) Pos 

func (x *BadExpr) Pos() token.Pos

type BasicLit 

type BasicLit struct {
	ValuePos token.Pos   // literal position
	Kind     token.Token // INT, FLOAT, DURATION, or STRING
	Value    string      // literal string; e.g. 42, 0x7f, 3.14, 1_234_567, 1e-9, 2.4i, 'a', '\x7f', "foo", or '\m\n\o'
	// contains filtered or unexported fields
}

A BasicLit node represents a literal of basic type.

func (*BasicLit) AddComment 

func (c *BasicLit) AddComment(cg *CommentGroup)

func (*BasicLit) Comments 

func (c *BasicLit) Comments() []*CommentGroup

func (*BasicLit) End 

func (x *BasicLit) End() token.Pos

func (*BasicLit) Pos 

func (x *BasicLit) Pos() token.Pos

type BinaryExpr 

type BinaryExpr struct {
	X     Expr        // left operand
	OpPos token.Pos   // position of Op
	Op    token.Token // operator
	Y     Expr        // right operand
	// contains filtered or unexported fields
}

A BinaryExpr node represents a binary expression.

func (*BinaryExpr) AddComment 

func (c *BinaryExpr) AddComment(cg *CommentGroup)

func (*BinaryExpr) Comments 

func (c *BinaryExpr) Comments() []*CommentGroup

func (*BinaryExpr) End 

func (x *BinaryExpr) End() token.Pos

func (*BinaryExpr) Pos 

func (x *BinaryExpr) Pos() token.Pos

type BottomLit 

type BottomLit struct {
	Bottom token.Pos
	// contains filtered or unexported fields
}

A BottomLit indicates an error.

func (*BottomLit) AddComment 

func (c *BottomLit) AddComment(cg *CommentGroup)

func (*BottomLit) Comments 

func (c *BottomLit) Comments() []*CommentGroup

func (*BottomLit) End 

func (x *BottomLit) End() token.Pos

func (*BottomLit) Pos 

func (x *BottomLit) Pos() token.Pos

type CallExpr 

type CallExpr struct {
	Fun    Expr      // function expression
	Lparen token.Pos // position of "("
	Args   []Expr    // function arguments; or nil
	Rparen token.Pos // position of ")"
	// contains filtered or unexported fields
}

A CallExpr node represents an expression followed by an argument list.

func (*CallExpr) AddComment 

func (c *CallExpr) AddComment(cg *CommentGroup)

func (*CallExpr) Comments 

func (c *CallExpr) Comments() []*CommentGroup

func (*CallExpr) End 

func (x *CallExpr) End() token.Pos

func (*CallExpr) Pos 

func (x *CallExpr) Pos() token.Pos

type Clause 

type Clause interface {
	Node
	// contains filtered or unexported methods
}

Clause nodes are part of comprehensions.

type Comment 

type Comment struct {
	Slash token.Pos // position of "/" starting the comment
	Text  string    // comment text (excluding '\n' for //-style comments)
}

A Comment node represents a single //-style or /*-style comment.

func (*Comment) AddComment 

func (g *Comment) AddComment(*CommentGroup)

func (*Comment) Comments 

func (g *Comment) Comments() []*CommentGroup

func (*Comment) End 

func (c *Comment) End() token.Pos

func (*Comment) Pos 

func (c *Comment) Pos() token.Pos

type CommentGroup 

type CommentGroup struct {
	// TODO: remove and use the token position of the first comment.
	Doc  bool
	Line bool // true if it is on the same line as the node's end pos.

	// Position indicates where a comment should be attached if a node has
	// multiple tokens. 0 means before the first token, 1 means before the
	// second, etc. For instance, for a field, the positions are:
	//    <0> Label <1> ":" <2> Expr <3> "," <4>
	Position int8
	List     []*Comment // len(List) > 0
}

A CommentGroup represents a sequence of comments with no other tokens and no empty lines between.

func (*CommentGroup) AddComment 

func (g *CommentGroup) AddComment(*CommentGroup)

func (*CommentGroup) Comments 

func (g *CommentGroup) Comments() []*CommentGroup

func (*CommentGroup) End 

func (g *CommentGroup) End() token.Pos

func (*CommentGroup) Pos 

func (g *CommentGroup) Pos() token.Pos

func (*CommentGroup) Text 

func (g *CommentGroup) Text() string

Text returns the text of the comment. Comment markers (//, /*, and */), the first space of a line comment, and leading and trailing empty lines are removed. Multiple empty lines are reduced to one, and trailing space on lines is trimmed. Unless the result is empty, it is newline-terminated.

type ComprehensionDecl 

type ComprehensionDecl struct {
	Field   *Field
	Select  token.Pos
	Clauses []Clause
	// contains filtered or unexported fields
}

A ComprehensionDecl node represents a field comprehension.

func (*ComprehensionDecl) AddComment 

func (c *ComprehensionDecl) AddComment(cg *CommentGroup)

func (*ComprehensionDecl) Comments 

func (c *ComprehensionDecl) Comments() []*CommentGroup

func (*ComprehensionDecl) End 

func (x *ComprehensionDecl) End() token.Pos

func (*ComprehensionDecl) Pos 

func (x *ComprehensionDecl) Pos() token.Pos

type Decl 

type Decl interface {
	Node
	// contains filtered or unexported methods
}

A Decl node is implemented by all declarations.

type EmitDecl 

type EmitDecl struct {
	Expr Expr
	// contains filtered or unexported fields
}

An EmitDecl node represents a single expression used as a declaration. The expressions in this declaration is what will be emitted as configuration output.

An EmitDecl may only appear at the top level.

func (*EmitDecl) AddComment 

func (c *EmitDecl) AddComment(cg *CommentGroup)

func (*EmitDecl) Comments 

func (c *EmitDecl) Comments() []*CommentGroup

func (*EmitDecl) End 

func (d *EmitDecl) End() token.Pos

func (*EmitDecl) Pos 

func (d *EmitDecl) Pos() token.Pos

type Expr 

type Expr interface {
	Node
	// contains filtered or unexported methods
}

An Expr is implemented by all expression nodes.

type Field 

type Field struct {
	Label    Label // must have at least one element.
	Optional token.Pos

	// No colon: Value must be an StructLit with one field.
	Colon token.Pos
	Value Expr // the value associated with this field.

	Attrs []*Attribute
	// contains filtered or unexported fields
}

A Field represents a field declaration in a struct.

func (*Field) AddComment 

func (c *Field) AddComment(cg *CommentGroup)

func (*Field) Comments 

func (c *Field) Comments() []*CommentGroup

func (*Field) End 

func (d *Field) End() token.Pos

func (*Field) Pos 

func (d *Field) Pos() token.Pos

type File 

type File struct {
	Filename string

	Package token.Pos // position of "package" pseudo-keyword
	Name    *Ident    // package names
	Decls   []Decl    // top-level declarations; or nil

	// TODO: Change Expr to Decl?
	Imports    []*ImportSpec // imports in this file
	Unresolved []*Ident      // unresolved identifiers in this file
	// contains filtered or unexported fields
}

A File node represents a Go source file.

The Comments list contains all comments in the source file in order of appearance, including the comments that are pointed to from other nodes via Doc and Comment fields.

func (*File) AddComment 

func (c *File) AddComment(cg *CommentGroup)

func (*File) Comments 

func (c *File) Comments() []*CommentGroup

func (*File) End 

func (f *File) End() token.Pos

func (*File) Pos 

func (f *File) Pos() token.Pos

type ForClause 

type ForClause struct {
	For    token.Pos
	Key    *Ident // allow pattern matching?
	Colon  token.Pos
	Value  *Ident // allow pattern matching?
	In     token.Pos
	Source Expr
	// contains filtered or unexported fields
}

A ForClause node represents a for clause in a comprehension.

func (*ForClause) AddComment 

func (c *ForClause) AddComment(cg *CommentGroup)

func (*ForClause) Comments 

func (c *ForClause) Comments() []*CommentGroup

func (*ForClause) End 

func (x *ForClause) End() token.Pos

func (*ForClause) Pos 

func (x *ForClause) Pos() token.Pos

type Ident 

type Ident struct {
	NamePos token.Pos // identifier position

	// This LHS path element may be an identifier. Possible forms:
	//  foo:    a normal identifier
	//  "foo":  JSON compatible
	//  <foo>:  a template shorthand
	Name string

	Scope Node // scope in which node was found or nil if referring directly
	Node  Node
	// contains filtered or unexported fields
}

An Ident node represents an left-hand side identifier.

func NewIdent 

func NewIdent(name string) *Ident

NewIdent creates a new Ident without position. Useful for ASTs generated by code other than the Go

func (*Ident) AddComment 

func (c *Ident) AddComment(cg *CommentGroup)

func (*Ident) Comments 

func (c *Ident) Comments() []*CommentGroup

func (*Ident) End 

func (x *Ident) End() token.Pos

func (*Ident) Pos 

func (x *Ident) Pos() token.Pos

func (*Ident) String 

func (id *Ident) String() string

type IfClause 

type IfClause struct {
	If        token.Pos
	Condition Expr
	// contains filtered or unexported fields
}

A IfClause node represents an if guard clause in a comprehension.

func (*IfClause) AddComment 

func (c *IfClause) AddComment(cg *CommentGroup)

func (*IfClause) Comments 

func (c *IfClause) Comments() []*CommentGroup

func (*IfClause) End 

func (x *IfClause) End() token.Pos

func (*IfClause) Pos 

func (x *IfClause) Pos() token.Pos

type ImportDecl 

type ImportDecl struct {
	Import token.Pos
	Lparen token.Pos // position of '(', if any
	Specs  []*ImportSpec
	Rparen token.Pos // position of ')', if any
	// contains filtered or unexported fields
}

A ImportDecl node represents a series of import declarations. A valid Lparen position (Lparen.Line > 0) indicates a parenthesized declaration.

func (*ImportDecl) AddComment 

func (c *ImportDecl) AddComment(cg *CommentGroup)

func (*ImportDecl) Comments 

func (c *ImportDecl) Comments() []*CommentGroup

func (*ImportDecl) End 

func (d *ImportDecl) End() token.Pos

func (*ImportDecl) Pos 

func (d *ImportDecl) Pos() token.Pos

type ImportSpec 

type ImportSpec struct {
	Name   *Ident    // local package name (including "."); or nil
	Path   *BasicLit // import path
	EndPos token.Pos // end of spec (overrides Path.Pos if nonzero)
	// contains filtered or unexported fields
}

An ImportSpec node represents a single package import.

func (*ImportSpec) AddComment 

func (c *ImportSpec) AddComment(cg *CommentGroup)

func (*ImportSpec) Comments 

func (c *ImportSpec) Comments() []*CommentGroup

func (*ImportSpec) End 

func (s *ImportSpec) End() token.Pos

func (*ImportSpec) Pos 

func (s *ImportSpec) Pos() token.Pos

type IndexExpr 

type IndexExpr struct {
	X      Expr      // expression
	Lbrack token.Pos // position of "["
	Index  Expr      // index expression
	Rbrack token.Pos // position of "]"
	// contains filtered or unexported fields
}

An IndexExpr node represents an expression followed by an index.

func (*IndexExpr) AddComment 

func (c *IndexExpr) AddComment(cg *CommentGroup)

func (*IndexExpr) Comments 

func (c *IndexExpr) Comments() []*CommentGroup

func (*IndexExpr) End 

func (x *IndexExpr) End() token.Pos

func (*IndexExpr) Pos 

func (x *IndexExpr) Pos() token.Pos

type Interpolation 

type Interpolation struct {
	Elts []Expr // interleaving of strings and expressions.
	// contains filtered or unexported fields
}

A Interpolation node represents a string or bytes interpolation.

func (*Interpolation) AddComment 

func (c *Interpolation) AddComment(cg *CommentGroup)

func (*Interpolation) Comments 

func (c *Interpolation) Comments() []*CommentGroup

func (*Interpolation) End 

func (x *Interpolation) End() token.Pos

func (*Interpolation) Pos 

func (x *Interpolation) Pos() token.Pos

type Label 

type Label interface {
	Node
	// contains filtered or unexported methods
}

A Label is any prduction that can be used as a LHS label.

type ListComprehension 

type ListComprehension struct {
	Lbrack  token.Pos // position of "["
	Expr    Expr
	Clauses []Clause  // Feed or Guard (TODO let)
	Rbrack  token.Pos // position of "]"
	// contains filtered or unexported fields
}

A ListComprehension node represents as list comprehension.

func (*ListComprehension) AddComment 

func (c *ListComprehension) AddComment(cg *CommentGroup)

func (*ListComprehension) Comments 

func (c *ListComprehension) Comments() []*CommentGroup

func (*ListComprehension) End 

func (x *ListComprehension) End() token.Pos

func (*ListComprehension) Pos 

func (x *ListComprehension) Pos() token.Pos

type ListLit 

type ListLit struct {
	Lbrack   token.Pos // position of "["
	Elts     []Expr    // list of composite elements; or nil
	Ellipsis token.Pos // open list if set
	Type     Expr      // type for the remaining elements
	Rbrack   token.Pos // position of "]"
	// contains filtered or unexported fields
}

A ListLit node represents a literal list.

func (*ListLit) AddComment 

func (c *ListLit) AddComment(cg *CommentGroup)

func (*ListLit) Comments 

func (c *ListLit) Comments() []*CommentGroup

func (*ListLit) End 

func (x *ListLit) End() token.Pos

func (*ListLit) Pos 

func (x *ListLit) Pos() token.Pos

type Node 

type Node interface {
	Pos() token.Pos // position of first character belonging to the node
	End() token.Pos // position of first character immediately after the node

	Comments() []*CommentGroup
	AddComment(*CommentGroup)
}

A Node represents any node in the abstract syntax tree.

type ParenExpr 

type ParenExpr struct {
	Lparen token.Pos // position of "("
	X      Expr      // parenthesized expression
	Rparen token.Pos // position of ")"
	// contains filtered or unexported fields
}

A ParenExpr node represents a parenthesized expression.

func (*ParenExpr) AddComment 

func (c *ParenExpr) AddComment(cg *CommentGroup)

func (*ParenExpr) Comments 

func (c *ParenExpr) Comments() []*CommentGroup

func (*ParenExpr) End 

func (x *ParenExpr) End() token.Pos

func (*ParenExpr) Pos 

func (x *ParenExpr) Pos() token.Pos

type SelectorExpr 

type SelectorExpr struct {
	X   Expr   // expression
	Sel *Ident // field selector
	// contains filtered or unexported fields
}

A SelectorExpr node represents an expression followed by a selector.

func (*SelectorExpr) AddComment 

func (c *SelectorExpr) AddComment(cg *CommentGroup)

func (*SelectorExpr) Comments 

func (c *SelectorExpr) Comments() []*CommentGroup

func (*SelectorExpr) End 

func (x *SelectorExpr) End() token.Pos

func (*SelectorExpr) Pos 

func (x *SelectorExpr) Pos() token.Pos

type SliceExpr 

type SliceExpr struct {
	X      Expr      // expression
	Lbrack token.Pos // position of "["
	Low    Expr      // begin of slice range; or nil
	High   Expr      // end of slice range; or nil
	Rbrack token.Pos // position of "]"
	// contains filtered or unexported fields
}

An SliceExpr node represents an expression followed by slice indices.

func (*SliceExpr) AddComment 

func (c *SliceExpr) AddComment(cg *CommentGroup)

func (*SliceExpr) Comments 

func (c *SliceExpr) Comments() []*CommentGroup

func (*SliceExpr) End 

func (x *SliceExpr) End() token.Pos

func (*SliceExpr) Pos 

func (x *SliceExpr) Pos() token.Pos

type StructLit 

type StructLit struct {
	Lbrace token.Pos // position of "{"
	Elts   []Decl    // list of elements; or nil
	Rbrace token.Pos // position of "}"
	// contains filtered or unexported fields
}

A StructLit node represents a literal struct.

func (*StructLit) AddComment 

func (c *StructLit) AddComment(cg *CommentGroup)

func (*StructLit) Comments 

func (c *StructLit) Comments() []*CommentGroup

func (*StructLit) End 

func (x *StructLit) End() token.Pos

func (*StructLit) Pos 

func (x *StructLit) Pos() token.Pos

type TemplateLabel 

type TemplateLabel struct {
	Langle token.Pos
	Ident  *Ident
	Rangle token.Pos
	// contains filtered or unexported fields
}

A TemplateLabel represents a field template declaration in a struct.

func (*TemplateLabel) AddComment 

func (c *TemplateLabel) AddComment(cg *CommentGroup)

func (*TemplateLabel) Comments 

func (c *TemplateLabel) Comments() []*CommentGroup

func (*TemplateLabel) End 

func (x *TemplateLabel) End() token.Pos

func (*TemplateLabel) Pos 

func (x *TemplateLabel) Pos() token.Pos

type UnaryExpr 

type UnaryExpr struct {
	OpPos token.Pos   // position of Op
	Op    token.Token // operator
	X     Expr        // operand
	// contains filtered or unexported fields
}

A UnaryExpr node represents a unary expression.

func (*UnaryExpr) AddComment 

func (c *UnaryExpr) AddComment(cg *CommentGroup)

func (*UnaryExpr) Comments 

func (c *UnaryExpr) Comments() []*CommentGroup

func (*UnaryExpr) End 

func (x *UnaryExpr) End() token.Pos

func (*UnaryExpr) Pos 

func (x *UnaryExpr) Pos() token.Pos

Source Files

View all Source files

Jump to

Keyboard shortcuts

? : This menu
/ : Search site
f or F : Jump to
y or Y : Canonical URL
go.dev uses cookies from Google to deliver and enhance the quality of its services and to analyze traffic. Learn more.