ast

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Published: Aug 2, 2020 License: MIT Imports: 3 Imported by: 0

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Index

Constants

This section is empty.

Variables

View Source
var OpTable = []opTableEntry{

	{"+", LPrefix, false},
	{"-", LPrefix, false},
	{"~", LPrefix, false},
	{"!", LPrefix, false},
	{"void", LPrefix, true},
	{"typeof", LPrefix, true},
	{"delete", LPrefix, true},

	{"--", LPrefix, false},
	{"++", LPrefix, false},

	{"--", LPostfix, false},
	{"++", LPostfix, false},

	{"+", LAdd, false},
	{"-", LAdd, false},
	{"*", LMultiply, false},
	{"/", LMultiply, false},
	{"%", LMultiply, false},
	{"**", LExponentiation, false},
	{"<", LCompare, false},
	{"<=", LCompare, false},
	{">", LCompare, false},
	{">=", LCompare, false},
	{"in", LCompare, true},
	{"instanceof", LCompare, true},
	{"<<", LShift, false},
	{">>", LShift, false},
	{">>>", LShift, false},
	{"==", LEquals, false},
	{"!=", LEquals, false},
	{"===", LEquals, false},
	{"!==", LEquals, false},
	{"??", LNullishCoalescing, false},
	{"||", LLogicalOr, false},
	{"&&", LLogicalAnd, false},
	{"|", LBitwiseOr, false},
	{"&", LBitwiseAnd, false},
	{"^", LBitwiseXor, false},

	{",", LComma, false},

	{"=", LAssign, false},
	{"+=", LAssign, false},
	{"-=", LAssign, false},
	{"*=", LAssign, false},
	{"/=", LAssign, false},
	{"%=", LAssign, false},
	{"**=", LAssign, false},
	{"<<=", LAssign, false},
	{">>=", LAssign, false},
	{">>>=", LAssign, false},
	{"|=", LAssign, false},
	{"&=", LAssign, false},
	{"^=", LAssign, false},
	{"??=", LAssign, false},
	{"||=", LAssign, false},
	{"&&=", LAssign, false},
}

Functions

func FollowAllSymbols

func FollowAllSymbols(symbols SymbolMap)

Use this before calling "FollowSymbols" from separate threads to avoid concurrent map update hazards. In Go, mutating a map is not threadsafe but reading from a map is. Calling "FollowAllSymbols" first ensures that all mutation is done up front.

func GenerateNonUniqueNameFromPath

func GenerateNonUniqueNameFromPath(path string) string

For readability, the names of certain automatically-generated symbols are derived from the file name. For example, instead of the CommonJS wrapper for a file being called something like "require273" it can be called something like "require_react" instead. This function generates the part of these identifiers that's specific to the file path. It can take both an absolute path (OS-specific) and a path in the source code (OS-independent).

Note that these generated names do not at all relate to the correctness of the code as far as avoiding symbol name collisions. These names still go through the renaming logic that all other symbols go through to avoid name collisions.

func IsSuperCall

func IsSuperCall(stmt Stmt) bool

Types

type AST

type AST struct {
	HasLazyExport bool

	// This is a list of CommonJS features. When a file uses CommonJS features,
	// it's not a candidate for "flat bundling" and must be wrapped in its own
	// closure.
	HasTopLevelReturn bool
	UsesExportsRef    bool
	UsesModuleRef     bool

	// This is a list of ES6 features
	HasES6Imports bool
	HasES6Exports bool

	Hashbang    string
	Directive   string
	Parts       []Part
	Symbols     SymbolMap
	ModuleScope *Scope
	ExportsRef  Ref
	ModuleRef   Ref
	WrapperRef  Ref

	// These are stored at the AST level instead of on individual AST nodes so
	// they can be manipulated efficiently without a full AST traversal
	ImportRecords []ImportRecord

	// These are used when bundling. They are filled in during the parser pass
	// since we already have to traverse the AST then anyway and the parser pass
	// is conveniently fully parallelized.
	NamedImports            map[Ref]NamedImport
	NamedExports            map[string]Ref
	TopLevelSymbolToParts   map[Ref][]uint32
	ExportStarImportRecords []uint32

	SourceMapComment Span
	SourceMap        *sourcemap.SourceMap
}

func (*AST) HasCommonJSFeatures added in v0.4.0

func (ast *AST) HasCommonJSFeatures() bool

func (*AST) HasES6Syntax added in v0.4.0

func (ast *AST) HasES6Syntax() bool

func (*AST) UsesCommonJSExports added in v0.4.0

func (ast *AST) UsesCommonJSExports() bool

type Arg

type Arg struct {
	TSDecorators []Expr
	Binding      Binding
	Default      *Expr

	// "constructor(public x: boolean) {}"
	IsTypeScriptCtorField bool
}

type ArrayBinding

type ArrayBinding struct {
	Binding      Binding
	DefaultValue *Expr
}

type AssignTarget added in v0.5.9

type AssignTarget uint8
const (
	AssignTargetNone    AssignTarget = iota
	AssignTargetReplace              // "a = b"
	AssignTargetUpdate               // "a += b"
)

type B

type B interface {
	// contains filtered or unexported methods
}

This interface is never called. Its purpose is to encode a variant type in Go's type system.

type BArray

type BArray struct {
	Items        []ArrayBinding
	HasSpread    bool
	IsSingleLine bool
}

type BIdentifier

type BIdentifier struct{ Ref Ref }

type BMissing

type BMissing struct{}

type BObject

type BObject struct {
	Properties   []PropertyBinding
	IsSingleLine bool
}

type Binding

type Binding struct {
	Loc  Loc
	Data B
}

type Case

type Case struct {
	Value *Expr
	Body  []Stmt
}

type Catch

type Catch struct {
	Loc     Loc
	Binding *Binding
	Body    []Stmt
}

type Class

type Class struct {
	TSDecorators []Expr
	Name         *LocRef
	Extends      *Expr
	BodyLoc      Loc
	Properties   []Property
}

type ClauseItem

type ClauseItem struct {
	Alias    string
	AliasLoc Loc
	Name     LocRef

	// This is needed for "export {foo as bar} from 'path'" statements. This case
	// is a re-export and "foo" and "bar" are both aliases. We need to preserve
	// both aliases in case the symbol is renamed.
	OriginalName string
}

type Decl

type Decl struct {
	Binding Binding
	Value   *Expr
}

type DeclaredSymbol added in v0.4.0

type DeclaredSymbol struct {
	Ref        Ref
	IsTopLevel bool
}

type E

type E interface {
	// contains filtered or unexported methods
}

This interface is never called. Its purpose is to encode a variant type in Go's type system.

type EArray

type EArray struct {
	Items        []Expr
	IsSingleLine bool
}

type EArrow

type EArrow struct {
	IsAsync         bool
	Args            []Arg
	HasRestArg      bool
	IsParenthesized bool
	PreferExpr      bool // Use shorthand if true and "Body" is a single return statement
	Body            FnBody
}

type EAwait

type EAwait struct {
	Value Expr
}

type EBigInt

type EBigInt struct{ Value string }

type EBinary

type EBinary struct {
	Op    OpCode
	Left  Expr
	Right Expr
}

type EBoolean

type EBoolean struct{ Value bool }

type ECall

type ECall struct {
	Target        Expr
	Args          []Expr
	OptionalChain OptionalChain
	IsDirectEval  bool

	// True if there is a comment containing "@__PURE__" or "#__PURE__" preceding
	// this call expression. This is an annotation used for tree shaking, and
	// means that the call can be removed if it's unused. It does not mean the
	// call is pure (e.g. it may still return something different if called twice).
	//
	// Note that the arguments are not considered to be part of the call. If the
	// call itself is removed due to this annotation, the arguments must remain
	// if they have side effects.
	CanBeUnwrappedIfUnused bool
}

type EClass

type EClass struct{ Class Class }

type EDot

type EDot struct {
	Target        Expr
	Name          string
	NameLoc       Loc
	OptionalChain OptionalChain

	// If true, this property access is known to be free of side-effects. That
	// means it can be removed if the resulting value isn't used.
	CanBeRemovedIfUnused bool

	// If true, this property access is a function that, when called, can be
	// unwrapped if the resulting value is unused. Unwrapping means discarding
	// the call target but keeping any arguments with side effects.
	CallCanBeUnwrappedIfUnused bool
}

type EFunction

type EFunction struct{ Fn Fn }

type EIdentifier

type EIdentifier struct {
	Ref Ref

	// If true, this identifier is known to not have a side effect (i.e. to not
	// throw an exception) when referenced. If false, this identifier may or may
	// not have side effects when referenced. This is used to allow the removal
	// of known globals such as "Object" if they aren't used.
	CanBeRemovedIfUnused bool

	// If true, this identifier represents a function that, when called, can be
	// unwrapped if the resulting value is unused. Unwrapping means discarding
	// the call target but keeping any arguments with side effects.
	CallCanBeUnwrappedIfUnused bool
}

type EIf

type EIf struct {
	Test Expr
	Yes  Expr
	No   Expr
}

type EImport

type EImport struct {
	Expr              Expr
	ImportRecordIndex *uint32
}

type EImportIdentifier

type EImportIdentifier struct {
	Ref Ref
}

This is similar to an EIdentifier but it represents a reference to an ES6 import item.

Depending on how the code is linked, the file containing this EImportIdentifier may or may not be in the same module group as the file it was imported from.

If it's the same module group than we can just merge the import item symbol with the corresponding symbol that was imported, effectively renaming them to be the same thing and statically binding them together.

But if it's a different module group, then the import must be dynamically evaluated using a property access off the corresponding namespace symbol, which represents the result of a require() call.

It's stored as a separate type so it's not easy to confuse with a plain identifier. For example, it'd be bad if code trying to convert "{x: x}" into "{x}" shorthand syntax wasn't aware that the "x" in this case is actually "{x: importedNamespace.x}". This separate type forces code to opt-in to doing this instead of opt-out.

type EImportMeta

type EImportMeta struct{}

type EIndex

type EIndex struct {
	Target        Expr
	Index         Expr
	OptionalChain OptionalChain
}

type EJSXElement

type EJSXElement struct {
	Tag        *Expr
	Properties []Property
	Children   []Expr
}

type EMissing

type EMissing struct{}

type ENew

type ENew struct {
	Target Expr
	Args   []Expr

	// True if there is a comment containing "@__PURE__" or "#__PURE__" preceding
	// this call expression. See the comment inside ECall for more details.
	CanBeUnwrappedIfUnused bool
}

type ENewTarget

type ENewTarget struct{}

type ENull

type ENull struct{}

type ENumber

type ENumber struct{ Value float64 }

type EObject

type EObject struct {
	Properties   []Property
	IsSingleLine bool
}

type EPrivateIdentifier added in v0.4.9

type EPrivateIdentifier struct {
	Ref Ref
}

This is similar to EIdentifier but it represents class-private fields and methods. It can be used where computed properties can be used, such as EIndex and Property.

type ERegExp

type ERegExp struct{ Value string }

type ERequire

type ERequire struct {
	ImportRecordIndex uint32
}

type ESpread

type ESpread struct{ Value Expr }

type EString

type EString struct{ Value []uint16 }

type ESuper

type ESuper struct{}

type ETemplate

type ETemplate struct {
	Tag     *Expr
	Head    []uint16
	HeadRaw string // This is only filled out for tagged template literals
	Parts   []TemplatePart
}

type EThis

type EThis struct{}

type EUnary

type EUnary struct {
	Op    OpCode
	Value Expr
}

type EUndefined

type EUndefined struct{}

type EYield

type EYield struct {
	Value  *Expr
	IsStar bool
}

type EnumValue

type EnumValue struct {
	Loc   Loc
	Ref   Ref
	Name  []uint16
	Value *Expr
}

type ExportStarAlias added in v0.4.12

type ExportStarAlias struct {
	Loc  Loc
	Name string
}

type Expr

type Expr struct {
	Loc  Loc
	Data E
}

func Assign added in v0.5.10

func Assign(a Expr, b Expr) Expr

func JoinAllWithComma

func JoinAllWithComma(all []Expr) Expr

func JoinWithComma

func JoinWithComma(a Expr, b Expr) Expr

type ExprOrStmt

type ExprOrStmt struct {
	Expr *Expr
	Stmt *Stmt
}

type Finally

type Finally struct {
	Loc   Loc
	Stmts []Stmt
}

type Fn

type Fn struct {
	Name         *LocRef
	Args         []Arg
	Body         FnBody
	ArgumentsRef Ref

	IsAsync     bool
	IsGenerator bool
	HasRestArg  bool
}

type FnBody

type FnBody struct {
	Loc   Loc
	Stmts []Stmt
}

type ImportItemStatus added in v0.4.0

type ImportItemStatus uint8
const (
	ImportItemNone ImportItemStatus = iota

	// The linker doesn't report import/export mismatch errors
	ImportItemGenerated

	// The printer will replace this import with "undefined"
	ImportItemMissing
)

type ImportKind

type ImportKind uint8
const (
	// An ES6 import or re-export statement
	ImportStmt ImportKind = iota

	// A call to "require()"
	ImportRequire

	// An "import()" expression with a string argument
	ImportDynamic
)

type ImportRecord added in v0.5.4

type ImportRecord struct {
	Loc  Loc
	Path Path

	// If this is an internal CommonJS import, this is the symbol of a function
	// that takes no arguments which, when called, implements require() for this
	// import. This is a wrapper function returned by "__commonJS()".
	WrapperRef Ref

	// The resolved source index for an internal import (within the bundle) or
	// nil for an external import (not included in the bundle)
	SourceIndex *uint32

	// If this is true, the import doesn't actually use any imported values. The
	// import is only used for its side effects.
	DoesNotUseExports bool

	// If true, this "export * from 'path'" statement is evaluated at run-time by
	// calling the "__exportStar()" helper function
	IsExportStarRunTimeEval bool

	// Tell the printer to wrap this call to "require()" in "__toModule(...)"
	WrapWithToModule bool

	// True for require calls like this: "try { require() } catch {}". In this
	// case we shouldn't generate an error if the path could not be resolved.
	IsInsideTryBody bool

	Kind ImportKind
}

type L

type L int
const (
	LLowest L = iota
	LComma
	LSpread
	LYield
	LAssign
	LConditional
	LNullishCoalescing
	LLogicalOr
	LLogicalAnd
	LBitwiseOr
	LBitwiseXor
	LBitwiseAnd
	LEquals
	LCompare
	LShift
	LAdd
	LMultiply
	LExponentiation
	LPrefix
	LPostfix
	LNew
	LCall
)

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Operator_Precedence

type Loc

type Loc struct {
	// This is the 0-based index of this location from the start of the file, in bytes
	Start int32
}

type LocRef

type LocRef struct {
	Loc Loc
	Ref Ref
}

type LocalKind

type LocalKind uint8
const (
	LocalVar LocalKind = iota
	LocalLet
	LocalConst
)

type NamedImport added in v0.4.0

type NamedImport struct {
	// Parts within this file that use this import
	LocalPartsWithUses []uint32

	Alias             string
	AliasLoc          Loc
	NamespaceRef      Ref
	ImportRecordIndex uint32

	// It's useful to flag exported imports because if they are in a TypeScript
	// file, we can't tell if they are a type or a value.
	IsExported bool
}

type NamespaceAlias

type NamespaceAlias struct {
	NamespaceRef Ref
	Alias        string
}

type OpCode

type OpCode int
const (
	// Prefix
	UnOpPos OpCode = iota
	UnOpNeg
	UnOpCpl
	UnOpNot
	UnOpVoid
	UnOpTypeof
	UnOpDelete

	// Prefix update
	UnOpPreDec
	UnOpPreInc

	// Postfix update
	UnOpPostDec
	UnOpPostInc

	// Left-associative
	BinOpAdd
	BinOpSub
	BinOpMul
	BinOpDiv
	BinOpRem
	BinOpPow
	BinOpLt
	BinOpLe
	BinOpGt
	BinOpGe
	BinOpIn
	BinOpInstanceof
	BinOpShl
	BinOpShr
	BinOpUShr
	BinOpLooseEq
	BinOpLooseNe
	BinOpStrictEq
	BinOpStrictNe
	BinOpNullishCoalescing
	BinOpLogicalOr
	BinOpLogicalAnd
	BinOpBitwiseOr
	BinOpBitwiseAnd
	BinOpBitwiseXor

	// Non-associative
	BinOpComma

	// Right-associative
	BinOpAssign
	BinOpAddAssign
	BinOpSubAssign
	BinOpMulAssign
	BinOpDivAssign
	BinOpRemAssign
	BinOpPowAssign
	BinOpShlAssign
	BinOpShrAssign
	BinOpUShrAssign
	BinOpBitwiseOrAssign
	BinOpBitwiseAndAssign
	BinOpBitwiseXorAssign
	BinOpNullishCoalescingAssign
	BinOpLogicalOrAssign
	BinOpLogicalAndAssign
)

If you add a new token, remember to add it to "OpTable" too

func (OpCode) BinaryAssignTarget added in v0.5.9

func (op OpCode) BinaryAssignTarget() AssignTarget

func (OpCode) IsLeftAssociative

func (op OpCode) IsLeftAssociative() bool

func (OpCode) IsPrefix

func (op OpCode) IsPrefix() bool

func (OpCode) IsRightAssociative

func (op OpCode) IsRightAssociative() bool

func (OpCode) UnaryAssignTarget added in v0.5.9

func (op OpCode) UnaryAssignTarget() AssignTarget

type OptionalChain added in v0.4.3

type OptionalChain uint8
const (
	// "a.b"
	OptionalChainNone OptionalChain = iota

	// "a?.b"
	OptionalChainStart

	// "a?.b.c" => ".c" is OptionalChainContinue
	// "(a?.b).c" => ".c" is OptionalChainNone
	OptionalChainContinue
)

type Part added in v0.4.0

type Part struct {
	Stmts []Stmt

	// Each is an index into the file-level import record list
	ImportRecordIndices []uint32

	// All symbols that are declared in this part. Note that a given symbol may
	// have multiple declarations, and so may end up being declared in multiple
	// parts (e.g. multiple "var" declarations with the same name). Also note
	// that this list isn't deduplicated and may contain duplicates.
	DeclaredSymbols []DeclaredSymbol

	// An estimate of the number of uses of all symbols used within this part.
	SymbolUses map[Ref]SymbolUse

	// The indices of the other parts in this file that are needed if this part
	// is needed.
	LocalDependencies map[uint32]bool

	// If true, this part can be removed if none of the declared symbols are
	// used. If the file containing this part is imported, then all parts that
	// don't have this flag enabled must be included.
	CanBeRemovedIfUnused bool

	// If true, this is the automatically-generated part for this file's ES6
	// exports. It may hold the "const exports = {};" statement and also the
	// "__export(exports, { ... })" call to initialize the getters.
	IsNamespaceExport bool

	// This is used for generated parts that we don't want to be present if they
	// aren't needed. This enables tree shaking for these parts even if global
	// tree shaking isn't enabled.
	ForceTreeShaking bool
}

Each file is made up of multiple parts, and each part consists of one or more top-level statements. Parts are used for tree shaking and code splitting analysis. Individual parts of a file can be discarded by tree shaking and can be assigned to separate chunks (i.e. output files) by code splitting.

type Path

type Path struct {
	Text       string
	IsAbsolute bool
}

This is used to represent both file system paths (IsAbsolute == true) and abstract module paths (IsAbsolute == false). Abstract module paths represent "virtual modules" when used for an input file and "package paths" when used to represent an external module.

func (Path) ComesBeforeInSortedOrder added in v0.5.26

func (a Path) ComesBeforeInSortedOrder(b Path) bool

type Property

type Property struct {
	TSDecorators []Expr
	Key          Expr

	// This is omitted for class fields
	Value *Expr

	// This is used when parsing a pattern that uses default values:
	//
	//   [a = 1] = [];
	//   ({a = 1} = {});
	//
	// It's also used for class fields:
	//
	//   class Foo { a = 1 }
	//
	Initializer *Expr

	Kind       PropertyKind
	IsComputed bool
	IsMethod   bool
	IsStatic   bool
}

type PropertyBinding

type PropertyBinding struct {
	IsComputed   bool
	IsSpread     bool
	Key          Expr
	Value        Binding
	DefaultValue *Expr
}

type PropertyKind

type PropertyKind int
const (
	PropertyNormal PropertyKind = iota
	PropertyGet
	PropertySet
	PropertySpread
)

type Range

type Range struct {
	Loc Loc
	Len int32
}

func (Range) End

func (r Range) End() int32

type Ref

type Ref struct {
	OuterIndex uint32
	InnerIndex uint32
}

Files are parsed in parallel for speed. We want to allow each parser to generate symbol IDs that won't conflict with each other. We also want to be able to quickly merge symbol tables from all files into one giant symbol table.

We can accomplish both goals by giving each symbol ID two parts: an outer index that is unique to the parser goroutine, and an inner index that increments as the parser generates new symbol IDs. Then a symbol map can be an array of arrays indexed first by outer index, then by inner index. The maps can be merged quickly by creating a single outer array containing all inner arrays from all parsed files.

var InvalidRef Ref = Ref{^uint32(0), ^uint32(0)}

func FollowSymbols

func FollowSymbols(symbols SymbolMap, ref Ref) Ref

Returns the canonical ref that represents the ref for the provided symbol. This may not be the provided ref if the symbol has been merged with another symbol.

func MergeSymbols

func MergeSymbols(symbols SymbolMap, old Ref, new Ref) Ref

Makes "old" point to "new" by joining the linked lists for the two symbols together. That way "FollowSymbols" on both "old" and "new" will result in the same ref.

type S

type S interface {
	// contains filtered or unexported methods
}

This interface is never called. Its purpose is to encode a variant type in Go's type system.

type SBlock

type SBlock struct {
	Stmts []Stmt
}

type SBreak

type SBreak struct {
	Name *LocRef
}

type SClass

type SClass struct {
	Class    Class
	IsExport bool
}

type SComment added in v0.5.23

type SComment struct {
	Text string
}

type SContinue

type SContinue struct {
	Name *LocRef
}

type SDebugger

type SDebugger struct{}

type SDirective

type SDirective struct {
	Value []uint16
}

type SDoWhile

type SDoWhile struct {
	Body Stmt
	Test Expr
}

type SEmpty

type SEmpty struct{}

type SEnum

type SEnum struct {
	Name     LocRef
	Arg      Ref
	Values   []EnumValue
	IsExport bool
}

type SExportClause

type SExportClause struct {
	Items        []ClauseItem
	IsSingleLine bool
}

type SExportDefault

type SExportDefault struct {
	DefaultName LocRef
	Value       ExprOrStmt // May be a SFunction or SClass
}

type SExportEquals

type SExportEquals struct {
	Value Expr
}

This is an "export = value;" statement in TypeScript

type SExportFrom

type SExportFrom struct {
	Items             []ClauseItem
	NamespaceRef      Ref
	ImportRecordIndex uint32
	IsSingleLine      bool
}

type SExportStar

type SExportStar struct {
	NamespaceRef      Ref
	Alias             *ExportStarAlias
	ImportRecordIndex uint32
}

type SExpr

type SExpr struct {
	Value Expr
}

type SFor

type SFor struct {
	Init   *Stmt // May be a SConst, SLet, SVar, or SExpr
	Test   *Expr
	Update *Expr
	Body   Stmt
}

type SForIn

type SForIn struct {
	Init  Stmt // May be a SConst, SLet, SVar, or SExpr
	Value Expr
	Body  Stmt
}

type SForOf

type SForOf struct {
	IsAwait bool
	Init    Stmt // May be a SConst, SLet, SVar, or SExpr
	Value   Expr
	Body    Stmt
}

type SFunction

type SFunction struct {
	Fn       Fn
	IsExport bool
}

type SIf

type SIf struct {
	Test Expr
	Yes  Stmt
	No   *Stmt
}

type SImport

type SImport struct {
	// If this is a star import: This is a Ref for the namespace symbol. The Loc
	// for the symbol is StarLoc.
	//
	// Otherwise: This is an auto-generated Ref for the namespace representing
	// the imported file. In this case StarLoc is nil. The NamespaceRef is used
	// when converting this module to a CommonJS module.
	NamespaceRef Ref

	DefaultName       *LocRef
	Items             *[]ClauseItem
	StarNameLoc       *Loc
	ImportRecordIndex uint32
	IsSingleLine      bool
}

This object represents all of these types of import statements:

import 'path'
import {item1, item2} from 'path'
import * as ns from 'path'
import defaultItem, {item1, item2} from 'path'
import defaultItem, * as ns from 'path'

Many parts are optional and can be combined in different ways. The only restriction is that you cannot have both a clause and a star namespace.

type SLabel

type SLabel struct {
	Name LocRef
	Stmt Stmt
}

type SLazyExport added in v0.5.24

type SLazyExport struct {
	Value Expr
}

The decision of whether to export an expression using "module.exports" or "export default" is deferred until linking using this statement kind

type SLocal

type SLocal struct {
	Decls    []Decl
	Kind     LocalKind
	IsExport bool

	// The TypeScript compiler doesn't generate code for "import foo = bar"
	// statements inside namespaces where the import is never used.
	WasTSImportEqualsInNamespace bool
}

type SNamespace

type SNamespace struct {
	Name     LocRef
	Arg      Ref
	Stmts    []Stmt
	IsExport bool
}

type SReturn

type SReturn struct {
	Value *Expr
}

type SSwitch

type SSwitch struct {
	Test    Expr
	BodyLoc Loc
	Cases   []Case
}

type SThrow

type SThrow struct {
	Value Expr
}

type STry

type STry struct {
	Body    []Stmt
	Catch   *Catch
	Finally *Finally
}

type STypeScript

type STypeScript struct{}

This is a stand-in for a TypeScript type declaration

type SWhile

type SWhile struct {
	Test Expr
	Body Stmt
}

type SWith

type SWith struct {
	Value   Expr
	BodyLoc Loc
	Body    Stmt
}

type Scope

type Scope struct {
	Kind      ScopeKind
	Parent    *Scope
	Children  []*Scope
	Members   map[string]Ref
	Generated []Ref

	// This is used to store the ref of the label symbol for ScopeLabel scopes.
	LabelRef Ref

	// If a scope contains a direct eval() expression, then none of the symbols
	// inside that scope can be renamed. We conservatively assume that the
	// evaluated code might reference anything that it has access to.
	ContainsDirectEval bool
}

type ScopeKind

type ScopeKind int
const (
	ScopeBlock ScopeKind = iota
	ScopeWith
	ScopeLabel
	ScopeClassName
	ScopeClassBody

	// The scopes below stop hoisted variables from extending into parent scopes
	ScopeEntry // This is a module, TypeScript enum, or TypeScript namespace
	ScopeFunctionArgs
	ScopeFunctionBody
)

func (ScopeKind) StopsHoisting

func (kind ScopeKind) StopsHoisting() bool

type Span added in v0.6.5

type Span struct {
	Text  string
	Range Range
}

type Stmt

type Stmt struct {
	Loc  Loc
	Data S
}

func AssignStmt added in v0.5.10

func AssignStmt(a Expr, b Expr) Stmt

type Symbol

type Symbol struct {
	Kind SymbolKind

	// Certain symbols must not be renamed or minified. For example, the
	// "arguments" variable is declared by the runtime for every function.
	// Renaming can also break any identifier used inside a "with" statement.
	MustNotBeRenamed bool

	// We automatically generate import items for property accesses off of
	// namespace imports. This lets us remove the expensive namespace imports
	// while bundling in many cases, replacing them with a cheap import item
	// instead:
	//
	//   import * as ns from 'path'
	//   ns.foo()
	//
	// That can often be replaced by this, which avoids needing the namespace:
	//
	//   import {foo} from 'path'
	//   foo()
	//
	// However, if the import is actually missing then we don't want to report a
	// compile-time error like we do for real import items. This status lets us
	// avoid this. We also need to be able to replace such import items with
	// undefined, which this status is also used for.
	ImportItemStatus ImportItemStatus

	// An estimate of the number of uses of this symbol. This is used for
	// minification (to prefer shorter names for more frequently used symbols).
	// The reason why this is an estimate instead of an accurate count is that
	// it's not updated during dead code elimination for speed. I figure that
	// even without updating after parsing it's still a pretty good heuristic.
	UseCountEstimate uint32

	Name string

	// Used by the parser for single pass parsing. Symbols that have been merged
	// form a linked-list where the last link is the symbol to use. This link is
	// an invalid ref if it's the last link. If this isn't invalid, you need to
	// FollowSymbols to get the real one.
	Link Ref

	// This is used for symbols that represent items in the import clause of an
	// ES6 import statement. These should always be referenced by EImportIdentifier
	// instead of an EIdentifier. When this is present, the expression should
	// be printed as a property access off the namespace instead of as a bare
	// identifier.
	//
	// For correctness, this must be stored on the symbol instead of indirectly
	// associated with the Ref for the symbol somehow. In ES6 "flat bundling"
	// mode, re-exported symbols are collapsed using MergeSymbols() and renamed
	// symbols from other files that end up at this symbol must be able to tell
	// if it has a namespace alias.
	NamespaceAlias *NamespaceAlias
}

type SymbolKind

type SymbolKind uint8
const (
	// An unbound symbol is one that isn't declared in the file it's referenced
	// in. For example, using "window" without declaring it will be unbound.
	SymbolUnbound SymbolKind = iota

	// This has special merging behavior. You're allowed to re-declare these
	// symbols more than once in the same scope. These symbols are also hoisted
	// out of the scope they are declared in to the closest containing function
	// or module scope. These are the symbols with this kind:
	//
	// - Function arguments
	// - Function statements
	// - Variables declared using "var"
	//
	SymbolHoisted
	SymbolHoistedFunction

	// There's a weird special case where catch variables declared using a simple
	// identifier (i.e. not a binding pattern) block hoisted variables instead of
	// becoming an error:
	//
	//   var e = 0;
	//   try { throw 1 } catch (e) {
	//     print(e) // 1
	//     var e = 2
	//     print(e) // 2
	//   }
	//   print(e) // 0 (since the hoisting stops at the catch block boundary)
	//
	// However, other forms are still a syntax error:
	//
	//   try {} catch (e) { let e }
	//   try {} catch ({e}) { var e }
	//
	// This symbol is for handling this weird special case.
	SymbolCatchIdentifier

	// Classes can merge with TypeScript namespaces.
	SymbolClass

	// A class-private identifier (i.e. "#foo").
	SymbolPrivateField
	SymbolPrivateMethod
	SymbolPrivateGet
	SymbolPrivateSet
	SymbolPrivateGetSetPair
	SymbolPrivateStaticField
	SymbolPrivateStaticMethod
	SymbolPrivateStaticGet
	SymbolPrivateStaticSet
	SymbolPrivateStaticGetSetPair

	// TypeScript enums can merge with TypeScript namespaces and other TypeScript
	// enums.
	SymbolTSEnum

	// TypeScript namespaces can merge with classes, functions, TypeScript enums,
	// and other TypeScript namespaces.
	SymbolTSNamespace

	// In TypeScript, imports are allowed to silently collide with symbols within
	// the module. Presumably this is because the imports may be type-only.
	SymbolImport

	// This annotates all other symbols that don't have special behavior.
	SymbolOther
)

func (SymbolKind) Feature added in v0.5.25

func (kind SymbolKind) Feature() compat.Feature

func (SymbolKind) IsHoisted

func (kind SymbolKind) IsHoisted() bool

func (SymbolKind) IsPrivate added in v0.4.9

func (kind SymbolKind) IsPrivate() bool

type SymbolMap

type SymbolMap struct {
	// This could be represented as a "map[Ref]Symbol" but a two-level array was
	// more efficient in profiles. This appears to be because it doesn't involve
	// a hash. This representation also makes it trivial to quickly merge symbol
	// maps from multiple files together. Each file only generates symbols in a
	// single inner array, so you can join the maps together by just make a
	// single outer array containing all of the inner arrays. See the comment on
	// "Ref" for more detail.
	Outer [][]Symbol
}

func NewSymbolMap

func NewSymbolMap(sourceCount int) SymbolMap

func (SymbolMap) Get

func (sm SymbolMap) Get(ref Ref) *Symbol

type SymbolUse added in v0.5.15

type SymbolUse struct {
	CountEstimate uint32
	IsAssigned    bool
}

type TemplatePart

type TemplatePart struct {
	Value   Expr
	Tail    []uint16
	TailRaw string // This is only filled out for tagged template literals
}

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