package parser

import "github.com/a-h/templ/parser/v2"

Index

Variables 

var ErrLegacyFileFormat = errors.New("legacy file format - run templ migrate")
var ErrNonSpaceCharacter = errors.New("non space character found")
var ErrTemplateNotFound = errors.New("template not found")

Functions

func ExpressionOf 

func ExpressionOf(p parse.Parser[string]) parse.Parser[Expression]

func StripType 

func StripType[T any](p parse.Parser[T]) parse.Parser[any]

StripType takes the parser and throws away the return value.

Types

type Attribute 

type Attribute interface {
	// Write out the string*.
	Write(w io.Writer, indent int) error
	Visit(v Visitor) error
	Copy() Attribute
}

func CopyAttributes 

func CopyAttributes(attrs []Attribute) (copies []Attribute)

type AttributeKey 

type AttributeKey interface {
	fmt.Stringer
}

type BoolConstantAttribute 

type BoolConstantAttribute struct {
	Key AttributeKey
}

<hr noshade/>

func (*BoolConstantAttribute) Copy 

func (bca *BoolConstantAttribute) Copy() Attribute

func (*BoolConstantAttribute) String 

func (bca *BoolConstantAttribute) String() string

func (*BoolConstantAttribute) Visit 

func (bca *BoolConstantAttribute) Visit(v Visitor) error

func (*BoolConstantAttribute) Write 

func (bca *BoolConstantAttribute) Write(w io.Writer, indent int) error

type BoolExpressionAttribute 

type BoolExpressionAttribute struct {
	Key        AttributeKey
	Expression Expression
}

noshade={ templ.Bool(...) }

func (*BoolExpressionAttribute) Copy 

func (bea *BoolExpressionAttribute) Copy() Attribute

func (*BoolExpressionAttribute) String 

func (bea *BoolExpressionAttribute) String() string

func (*BoolExpressionAttribute) Visit 

func (bea *BoolExpressionAttribute) Visit(v Visitor) error

func (*BoolExpressionAttribute) Write 

func (bea *BoolExpressionAttribute) Write(w io.Writer, indent int) error

type CSSProperty 

type CSSProperty interface {
	IsCSSProperty() bool
	Write(w io.Writer, indent int) error
	Visit(v Visitor) error
}

CSSProperty is a CSS property and value pair.

type CSSTemplate 

type CSSTemplate struct {
	Range      Range
	Name       string
	Expression Expression
	Properties []CSSProperty
}

CSS definition. 

css Name() {
  color: #ffffff;
  background-color: { constants.BackgroundColor };
  background-image: url('./somewhere.png');
}

func (*CSSTemplate) IsTemplateFileNode 

func (css *CSSTemplate) IsTemplateFileNode() bool

func (*CSSTemplate) Visit 

func (css *CSSTemplate) Visit(v Visitor) error

func (*CSSTemplate) Write 

func (css *CSSTemplate) Write(w io.Writer, indent int) error

type CallTemplateExpression 

type CallTemplateExpression struct {
	// Expression returns a template to execute.
	Expression Expression
}

CallTemplateExpression can be used to create and render a template using data. {! Other(p.First, p.Last) } or it can be used to render a template parameter. {! v }

func (*CallTemplateExpression) IsNode 

func (cte *CallTemplateExpression) IsNode() bool

func (*CallTemplateExpression) Visit 

func (cte *CallTemplateExpression) Visit(v Visitor) error

func (*CallTemplateExpression) Write 

func (cte *CallTemplateExpression) Write(w io.Writer, indent int) error

type CaseExpression 

type CaseExpression struct {
	Expression Expression
	Children   []Node
}

case "Something":

type ChildrenExpression 

type ChildrenExpression struct{}

ChildrenExpression can be used to rended the children of a templ element. { children ... }

func (*ChildrenExpression) IsNode 

func (*ChildrenExpression) IsNode() bool

func (*ChildrenExpression) Visit 

func (ce *ChildrenExpression) Visit(v Visitor) error

func (*ChildrenExpression) Write 

func (*ChildrenExpression) Write(w io.Writer, indent int) error

type CompositeNode 

type CompositeNode interface {
	Node
	ChildNodes() []Node
}

type ConditionalAttribute 

type ConditionalAttribute struct {
	Expression Expression
	Then       []Attribute
	Else       []Attribute
}
<a href="test" \
	if active {
   class="isActive"
 }

func (*ConditionalAttribute) Copy 

func (ca *ConditionalAttribute) Copy() Attribute

func (*ConditionalAttribute) String 

func (ca *ConditionalAttribute) String() string

func (*ConditionalAttribute) Visit 

func (ca *ConditionalAttribute) Visit(v Visitor) error

func (*ConditionalAttribute) Write 

func (ca *ConditionalAttribute) Write(w io.Writer, indent int) error

type ConstantAttribute 

type ConstantAttribute struct {
	Key         AttributeKey
	Value       string
	SingleQuote bool
}

href=""

func (*ConstantAttribute) Copy 

func (ca *ConstantAttribute) Copy() Attribute

func (*ConstantAttribute) String 

func (ca *ConstantAttribute) String() string

func (*ConstantAttribute) Visit 

func (ca *ConstantAttribute) Visit(v Visitor) error

func (*ConstantAttribute) Write 

func (ca *ConstantAttribute) Write(w io.Writer, indent int) error

type ConstantAttributeKey 

type ConstantAttributeKey struct {
	Name      string
	NameRange Range
}

func (ConstantAttributeKey) String 

func (c ConstantAttributeKey) String() string

type ConstantCSSProperty 

type ConstantCSSProperty struct {
	Name  string
	Value string
}

color: #ffffff;

func (*ConstantCSSProperty) IsCSSProperty 

func (c *ConstantCSSProperty) IsCSSProperty() bool

func (ConstantCSSProperty) String 

func (c ConstantCSSProperty) String(minified bool) string

func (*ConstantCSSProperty) Visit 

func (c *ConstantCSSProperty) Visit(v Visitor) error

func (*ConstantCSSProperty) Write 

func (c *ConstantCSSProperty) Write(w io.Writer, indent int) error

type Diagnostic 

type Diagnostic struct {
	Message string
	Range   Range
}

Diagnostic for template file.

func Diagnose 

func Diagnose(t *TemplateFile) ([]Diagnostic, error)

type DocType 

type DocType struct {
	Value string
}

<!DOCTYPE html>

func (*DocType) IsNode 

func (dt *DocType) IsNode() bool

func (*DocType) Visit 

func (dt *DocType) Visit(v Visitor) error

func (*DocType) Write 

func (dt *DocType) Write(w io.Writer, indent int) error

type Element 

type Element struct {
	Name           string
	Attributes     []Attribute
	IndentAttrs    bool
	Children       []Node
	IndentChildren bool
	TrailingSpace  TrailingSpace
	NameRange      Range
}

<a .../> or <div ...>...</div>

func (Element) ChildNodes 

func (e Element) ChildNodes() []Node

func (Element) IsBlockElement 

func (e Element) IsBlockElement() bool

func (*Element) IsNode 

func (e *Element) IsNode() bool

func (Element) IsVoidElement 

func (e Element) IsVoidElement() bool

https://www.w3.org/TR/2011/WD-html-markup-20110113/syntax.html#void-element

func (Element) Trailing 

func (e Element) Trailing() TrailingSpace

func (Element) Validate 

func (e Element) Validate() (msgs []string, ok bool)

Validate that no invalid expressions have been used.

func (*Element) Visit 

func (e *Element) Visit(v Visitor) error

func (*Element) Write 

func (e *Element) Write(w io.Writer, indent int) error

type ElseIfExpression 

type ElseIfExpression struct {
	Expression Expression
	Then       []Node
}

type Expression 

type Expression struct {
	Value string
	Range Range
}

Expression containing Go code.

func NewExpression 

func NewExpression(value string, from, to parse.Position) Expression

NewExpression creates a Go expression.

type ExpressionAttribute 

type ExpressionAttribute struct {
	Key        AttributeKey
	Expression Expression
}

href={ ... }

func (*ExpressionAttribute) Copy 

func (ea *ExpressionAttribute) Copy() Attribute

func (*ExpressionAttribute) String 

func (ea *ExpressionAttribute) String() string

func (*ExpressionAttribute) Visit 

func (ea *ExpressionAttribute) Visit(v Visitor) error

func (*ExpressionAttribute) Write 

func (ea *ExpressionAttribute) Write(w io.Writer, indent int) (err error)

type ExpressionAttributeKey 

type ExpressionAttributeKey struct {
	Expression Expression
}

func (ExpressionAttributeKey) String 

func (e ExpressionAttributeKey) String() string

type ExpressionCSSProperty 

type ExpressionCSSProperty struct {
	Name  string
	Value *StringExpression
}

background-color: { constants.BackgroundColor };

func (*ExpressionCSSProperty) IsCSSProperty 

func (c *ExpressionCSSProperty) IsCSSProperty() bool

func (*ExpressionCSSProperty) Visit 

func (c *ExpressionCSSProperty) Visit(v Visitor) error

func (*ExpressionCSSProperty) Write 

func (c *ExpressionCSSProperty) Write(w io.Writer, indent int) error

type ForExpression 

type ForExpression struct {
	Expression Expression
	Children   []Node
}
for i, v := range p.Addresses {
  {! Address(v) }
}

func (ForExpression) ChildNodes 

func (fe ForExpression) ChildNodes() []Node

func (*ForExpression) IsNode 

func (fe *ForExpression) IsNode() bool

func (*ForExpression) Visit 

func (fe *ForExpression) Visit(v Visitor) error

func (*ForExpression) Write 

func (fe *ForExpression) Write(w io.Writer, indent int) error

type GoCode 

type GoCode struct {
	Expression Expression
	// TrailingSpace lists what happens after the expression.
	TrailingSpace TrailingSpace
	Multiline     bool
}

GoCode is used within HTML elements, and allows arbitrary go code. {{ ... }}

func (*GoCode) IsNode 

func (gc *GoCode) IsNode() bool

func (*GoCode) Trailing 

func (gc *GoCode) Trailing() TrailingSpace

func (*GoCode) Visit 

func (gc *GoCode) Visit(v Visitor) error

func (*GoCode) Write 

func (gc *GoCode) Write(w io.Writer, indent int) error

type GoComment 

type GoComment struct {
	Contents  string
	Multiline bool
	Range     Range
}

GoComment.

func (*GoComment) IsNode 

func (c *GoComment) IsNode() bool

func (*GoComment) Visit 

func (c *GoComment) Visit(v Visitor) error

func (*GoComment) Write 

func (c *GoComment) Write(w io.Writer, indent int) error

type HTMLComment 

type HTMLComment struct {
	Contents string
}

HTMLComment.

func (*HTMLComment) IsNode 

func (c *HTMLComment) IsNode() bool

func (*HTMLComment) Visit 

func (c *HTMLComment) Visit(v Visitor) error

func (*HTMLComment) Write 

func (c *HTMLComment) Write(w io.Writer, indent int) error

type HTMLTemplate 

type HTMLTemplate struct {
	Range      Range
	Expression Expression
	Children   []Node
}

HTMLTemplate definition. 

templ Name(p Parameter) {
  if ... {
      <Element></Element>
  }
}

func (*HTMLTemplate) IsTemplateFileNode 

func (t *HTMLTemplate) IsTemplateFileNode() bool

func (*HTMLTemplate) Visit 

func (t *HTMLTemplate) Visit(v Visitor) error

func (*HTMLTemplate) Write 

func (t *HTMLTemplate) Write(w io.Writer, indent int) error

type IfExpression 

type IfExpression struct {
	Expression Expression
	Then       []Node
	ElseIfs    []ElseIfExpression
	Else       []Node
}

if p.Type == "test" && p.thing { }

func (IfExpression) ChildNodes 

func (n IfExpression) ChildNodes() []Node

func (*IfExpression) IsNode 

func (n *IfExpression) IsNode() bool

func (*IfExpression) Visit 

func (n *IfExpression) Visit(v Visitor) error

func (*IfExpression) Write 

func (n *IfExpression) Write(w io.Writer, indent int) error

type Node 

type Node interface {
	IsNode() bool
	// Write out the string*.
	Write(w io.Writer, indent int) error
	Visit(v Visitor) error
}

A Node appears within a template, e.g. an StringExpression, Element, IfExpression etc.

type Nodes 

type Nodes struct {
	Nodes []Node
}

type Package 

type Package struct {
	Expression Expression
}

func (*Package) Visit 

func (p *Package) Visit(v Visitor) error

func (*Package) Write 

func (p *Package) Write(w io.Writer, indent int) error

type Position 

type Position struct {
	Index int64
	Line  uint32
	Col   uint32
}

Source mapping to map from the source code of the template to the in-memory representation.

func NewPosition 

func NewPosition(index int64, line, col uint32) Position

NewPosition initialises a position.

func (*Position) String 

func (p *Position) String() string

type Range 

type Range struct {
	From Position
	To   Position
}

Range of text within a file.

func NewRange 

func NewRange(from, to parse.Position) Range

NewRange creates a Range expression.

type RawElement 

type RawElement struct {
	Name       string
	Attributes []Attribute
	Contents   string
}

func (*RawElement) IsNode 

func (e *RawElement) IsNode() bool

func (*RawElement) Visit 

func (e *RawElement) Visit(v Visitor) error

func (*RawElement) Write 

func (e *RawElement) Write(w io.Writer, indent int) error

type ScriptContents 

type ScriptContents struct {
	// Value is the raw script contents. This is nil if the Type is Go.
	Value *string
	// GoCode is the Go expression. This is nil if the Type is JS.
	GoCode *GoCode
	// InsideStringLiteral denotes how the result of any Go expression should be escaped in the output.
	//  - Not quoted: JSON encoded.
	//  - InsideStringLiteral: JS escaped (newlines become \n, `"' becomes \`\"\' etc.), HTML escaped so that a string can't contain </script>.
	InsideStringLiteral bool
}

func NewScriptContentsGo 

func NewScriptContentsGo(code *GoCode, insideStringLiteral bool) ScriptContents

func NewScriptContentsScriptCode 

func NewScriptContentsScriptCode(value string) ScriptContents

type ScriptElement 

type ScriptElement struct {
	Attributes []Attribute
	Contents   []ScriptContents
}

func (*ScriptElement) IsNode 

func (se *ScriptElement) IsNode() bool

func (*ScriptElement) Visit 

func (se *ScriptElement) Visit(v Visitor) error

func (*ScriptElement) Write 

func (se *ScriptElement) Write(w io.Writer, indent int) error

type ScriptTemplate 

type ScriptTemplate struct {
	Range      Range
	Name       Expression
	Parameters Expression
	Value      string
}

ScriptTemplate is a script block.

func (*ScriptTemplate) IsTemplateFileNode 

func (s *ScriptTemplate) IsTemplateFileNode() bool

func (*ScriptTemplate) Visit 

func (s *ScriptTemplate) Visit(v Visitor) error

func (*ScriptTemplate) Write 

func (s *ScriptTemplate) Write(w io.Writer, indent int) error

type SourceMap 

type SourceMap struct {
	Expressions               []string
	SourceLinesToTarget       map[uint32]map[uint32]Position
	TargetLinesToSource       map[uint32]map[uint32]Position
	SourceSymbolRangeToTarget map[uint32]map[uint32]Range
	TargetSymbolRangeToSource map[uint32]map[uint32]Range
}

func NewSourceMap 

func NewSourceMap() *SourceMap

NewSourceMap creates a new lookup to map templ source code to items in the parsed template.

func (*SourceMap) Add 

func (sm *SourceMap) Add(src Expression, tgt Range) (updatedFrom Position)

Add an item to the lookup.

func (*SourceMap) AddSymbolRange 

func (sm *SourceMap) AddSymbolRange(src Range, tgt Range)

func (*SourceMap) SourcePositionFromTarget 

func (sm *SourceMap) SourcePositionFromTarget(line, col uint32) (src Position, ok bool)

SourcePositionFromTarget looks the source position using the target position. If a source exists on the line but not the col, the function will search backwards.

func (*SourceMap) SymbolSourceRangeFromTarget 

func (sm *SourceMap) SymbolSourceRangeFromTarget(line, col uint32) (src Range, ok bool)

func (*SourceMap) SymbolTargetRangeFromSource 

func (sm *SourceMap) SymbolTargetRangeFromSource(line, col uint32) (tgt Range, ok bool)

func (*SourceMap) TargetPositionFromSource 

func (sm *SourceMap) TargetPositionFromSource(line, col uint32) (tgt Position, ok bool)

TargetPositionFromSource looks up the target position using the source position.

type SpreadAttributes 

type SpreadAttributes struct {
	Expression Expression
}

<a { spread... } />

func (*SpreadAttributes) Copy 

func (sa *SpreadAttributes) Copy() Attribute

func (*SpreadAttributes) String 

func (sa *SpreadAttributes) String() string

func (*SpreadAttributes) Visit 

func (sa *SpreadAttributes) Visit(v Visitor) error

func (*SpreadAttributes) Write 

func (sa *SpreadAttributes) Write(w io.Writer, indent int) error

type StringExpression 

type StringExpression struct {
	Expression Expression
	// TrailingSpace lists what happens after the expression.
	TrailingSpace TrailingSpace
}

StringExpression is used within HTML elements, and for style values. { ... }

func (*StringExpression) IsNode 

func (se *StringExpression) IsNode() bool

func (*StringExpression) IsStyleDeclarationValue 

func (se *StringExpression) IsStyleDeclarationValue() bool

func (*StringExpression) Trailing 

func (se *StringExpression) Trailing() TrailingSpace

func (*StringExpression) Visit 

func (se *StringExpression) Visit(v Visitor) error

func (*StringExpression) Write 

func (se *StringExpression) Write(w io.Writer, indent int) error

type SwitchExpression 

type SwitchExpression struct {
	Expression Expression
	Cases      []CaseExpression
}
switch p.Type {
 case "Something":
}

func (SwitchExpression) ChildNodes 

func (se SwitchExpression) ChildNodes() []Node

func (*SwitchExpression) IsNode 

func (se *SwitchExpression) IsNode() bool

func (*SwitchExpression) Visit 

func (se *SwitchExpression) Visit(v Visitor) error

func (*SwitchExpression) Write 

func (se *SwitchExpression) Write(w io.Writer, indent int) error

type TemplElementExpression 

type TemplElementExpression struct {
	// Expression returns a template to execute.
	Expression Expression
	// Children returns the elements in a block element.
	Children []Node
}

TemplElementExpression can be used to create and render a template using data. @Other(p.First, p.Last) or it can be used to render a template parameter. @v

func (TemplElementExpression) ChildNodes 

func (tee TemplElementExpression) ChildNodes() []Node

func (*TemplElementExpression) IsNode 

func (tee *TemplElementExpression) IsNode() bool

func (*TemplElementExpression) Visit 

func (tee *TemplElementExpression) Visit(v Visitor) error

func (*TemplElementExpression) Write 

func (tee *TemplElementExpression) Write(w io.Writer, indent int) error

type TemplateFile 

type TemplateFile struct {
	// Header contains comments or whitespace at the top of the file.
	Header []*TemplateFileGoExpression
	// Package expression.
	Package Package
	// Filepath is where the file was loaded from. It is not always available.
	Filepath string
	// Nodes in the file.
	Nodes []TemplateFileNode
}

func Parse 

func Parse(fileName string) (*TemplateFile, error)

func ParseString 

func ParseString(template string) (*TemplateFile, error)

func (*TemplateFile) Visit 

func (tf *TemplateFile) Visit(v Visitor) error

func (*TemplateFile) Write 

func (tf *TemplateFile) Write(w io.Writer) error

type TemplateFileGoExpression 

type TemplateFileGoExpression struct {
	Expression    Expression
	BeforePackage bool
}

TemplateFileGoExpression within a TemplateFile

func (*TemplateFileGoExpression) IsTemplateFileNode 

func (exp *TemplateFileGoExpression) IsTemplateFileNode() bool

func (*TemplateFileGoExpression) Visit 

func (exp *TemplateFileGoExpression) Visit(v Visitor) error

func (*TemplateFileGoExpression) Write 

func (exp *TemplateFileGoExpression) Write(w io.Writer, indent int) error

type TemplateFileNode 

type TemplateFileNode interface {
	IsTemplateFileNode() bool
	Write(w io.Writer, indent int) error
	Visit(v Visitor) error
}

TemplateFileNode can be a Template, CSS, Script or Go.

type TemplateFileParser 

type TemplateFileParser struct {
	DefaultPackage string
}

func NewTemplateFileParser 

func NewTemplateFileParser(pkg string) TemplateFileParser

NewTemplateFileParser creates a new TemplateFileParser.

func (TemplateFileParser) Parse 

func (p TemplateFileParser) Parse(pi *parse.Input) (tf *TemplateFile, matched bool, err error)

type Text 

type Text struct {
	// Range of the text within the templ file.
	Range Range
	// Value is the raw HTML encoded value.
	Value string
	// TrailingSpace lists what happens after the text.
	TrailingSpace TrailingSpace
}

Text node within the document.

func (*Text) IsNode 

func (t *Text) IsNode() bool

func (Text) Trailing 

func (t Text) Trailing() TrailingSpace

func (*Text) Visit 

func (t *Text) Visit(v Visitor) error

func (*Text) Write 

func (t *Text) Write(w io.Writer, indent int) error

type TrailingSpace 

type TrailingSpace string

TrailingSpace defines the whitespace that may trail behind the close of an element, a text node, or string expression. 

const (
	SpaceNone       TrailingSpace = ""
	SpaceHorizontal TrailingSpace = " "
	SpaceVertical   TrailingSpace = "\n"
)

func NewTrailingSpace 

func NewTrailingSpace(s string) (ts TrailingSpace, err error)

type UntilNotFoundError 

type UntilNotFoundError struct {
	parse.ParseError
}

type Visitor 

type Visitor interface {
	VisitTemplateFile(*TemplateFile) error
	VisitTemplateFileGoExpression(*TemplateFileGoExpression) error
	VisitPackage(*Package) error
	VisitWhitespace(*Whitespace) error
	VisitCSSTemplate(*CSSTemplate) error
	VisitConstantCSSProperty(*ConstantCSSProperty) error
	VisitExpressionCSSProperty(*ExpressionCSSProperty) error
	VisitDocType(*DocType) error
	VisitHTMLTemplate(*HTMLTemplate) error
	VisitText(*Text) error
	VisitElement(*Element) error
	VisitScriptElement(*ScriptElement) error
	VisitRawElement(*RawElement) error
	VisitBoolConstantAttribute(*BoolConstantAttribute) error
	VisitConstantAttribute(*ConstantAttribute) error
	VisitBoolExpressionAttribute(*BoolExpressionAttribute) error
	VisitExpressionAttribute(*ExpressionAttribute) error
	VisitSpreadAttributes(*SpreadAttributes) error
	VisitConditionalAttribute(*ConditionalAttribute) error
	VisitGoComment(*GoComment) error
	VisitHTMLComment(*HTMLComment) error
	VisitCallTemplateExpression(*CallTemplateExpression) error
	VisitTemplElementExpression(*TemplElementExpression) error
	VisitChildrenExpression(*ChildrenExpression) error
	VisitIfExpression(*IfExpression) error
	VisitSwitchExpression(*SwitchExpression) error
	VisitForExpression(*ForExpression) error
	VisitGoCode(*GoCode) error
	VisitStringExpression(*StringExpression) error
	VisitScriptTemplate(*ScriptTemplate) error
}

Visitor is an interface for visiting nodes in the parse tree.

type Whitespace 

type Whitespace struct {
	Value string
}

Whitespace.

func (*Whitespace) IsNode 

func (ws *Whitespace) IsNode() bool

func (*Whitespace) Visit 

func (ws *Whitespace) Visit(v Visitor) error

func (*Whitespace) Write 

func (ws *Whitespace) Write(w io.Writer, indent int) error

type WhitespaceTrailer 

type WhitespaceTrailer interface {
	Trailing() TrailingSpace
}

Source Files

calltemplateparser.go childrenparser.go conditionalattributeparser.go cssparser.go diagnostics.go doctypeparser.go elementparser.go expressionparser.go forexpressionparser.go gocodeparser.go gocommentparser.go goparser.go htmlcommentparser.go ifexpressionparser.go packageparser.go parser.go raw.go scriptparser.go scripttemplateparser.go sourcemap.go stringexpressionparser.go structure.go switchexpressionparser.go templatefile.go templateparser.go templelementparser.go textparser.go types.go visitor.go whitespaceparser.go

Directories

PathSynopsis
parser/v2/goexpression
parser/v2/visitor
Version
v0.3.924 (latest)
Published
Jul 26, 2025
Platform
linux/amd64
Imports
12 packages
Last checked
5 days ago –

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