Documentation ¶
Overview ¶
Package parse builds parse trees for templates as defined by text/template and html/template. Clients should use those packages to construct templates rather than this one, which provides shared internal data structures not intended for general use.
Index ¶
- func IsEmptyTree(n Node) bool
- func Parse(name, text, leftDelim, rightDelim string, funcs ...map[string]interface{}) (treeSet map[string]*Tree, err error)
- type ActionNode
- type BoolNode
- type BranchNode
- type ChainNode
- type CommandNode
- type DotNode
- type FieldNode
- type IdentifierNode
- type IfNode
- type ListNode
- type NilNode
- type Node
- type NodeType
- type NumberNode
- type PipeNode
- type Pos
- type RangeNode
- type StringNode
- type TemplateNode
- type TextNode
- type Tree
- type VariableNode
- type WithNode
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
func IsEmptyTree ¶
IsEmptyTree reports whether this tree (node) is empty of everything but space.
func Parse ¶
func Parse(name, text, leftDelim, rightDelim string, funcs ...map[string]interface{}) (treeSet map[string]*Tree, err error)
Parse returns a map from template name to parse.Tree, created by parsing the templates described in the argument string. The top-level template will be given the specified name. If an error is encountered, parsing stops and an empty map is returned with the error.
Types ¶
type ActionNode ¶
type ActionNode struct { NodeType Pos Line int // The line number in the input (deprecated; kept for compatibility) Pipe *PipeNode // The pipeline in the action. }
ActionNode holds an action (something bounded by delimiters). Control actions have their own nodes; ActionNode represents simple ones such as field evaluations and parenthesized pipelines.
func (*ActionNode) Copy ¶
func (a *ActionNode) Copy() Node
func (*ActionNode) String ¶
func (a *ActionNode) String() string
type BranchNode ¶
type BranchNode struct { NodeType Pos Line int // The line number in the input (deprecated; kept for compatibility) Pipe *PipeNode // The pipeline to be evaluated. List *ListNode // What to execute if the value is non-empty. ElseList *ListNode // What to execute if the value is empty (nil if absent). }
BranchNode is the common representation of if, range, and with.
func (*BranchNode) String ¶
func (b *BranchNode) String() string
type ChainNode ¶
type ChainNode struct { NodeType Pos Node Node Field []string // The identifiers in lexical order. }
ChainNode holds a term followed by a chain of field accesses (identifier starting with '.'). The names may be chained ('.x.y'). The periods are dropped from each ident.
type CommandNode ¶
type CommandNode struct { NodeType Pos Args []Node // Arguments in lexical order: Identifier, field, or constant. }
CommandNode holds a command (a pipeline inside an evaluating action).
func (*CommandNode) Copy ¶
func (c *CommandNode) Copy() Node
func (*CommandNode) String ¶
func (c *CommandNode) String() string
type FieldNode ¶
FieldNode holds a field (identifier starting with '.'). The names may be chained ('.x.y'). The period is dropped from each ident.
type IdentifierNode ¶
IdentifierNode holds an identifier.
func NewIdentifier ¶
func NewIdentifier(ident string) *IdentifierNode
NewIdentifier returns a new IdentifierNode with the given identifier name.
func (*IdentifierNode) Copy ¶
func (i *IdentifierNode) Copy() Node
func (*IdentifierNode) SetPos ¶
func (i *IdentifierNode) SetPos(pos Pos) *IdentifierNode
SetPos sets the position. NewIdentifier is a public method so we can't modify its signature. Chained for convenience. TODO: fix one day?
func (*IdentifierNode) String ¶
func (i *IdentifierNode) String() string
type IfNode ¶
type IfNode struct {
BranchNode
}
IfNode represents an {{if}} action and its commands.
type NilNode ¶
type NilNode struct {
Pos
}
NilNode holds the special identifier 'nil' representing an untyped nil constant.
type Node ¶
type Node interface { Type() NodeType String() string // Copy does a deep copy of the Node and all its components. // To avoid type assertions, some XxxNodes also have specialized // CopyXxx methods that return *XxxNode. Copy() Node Position() Pos // byte position of start of node in full original input string // contains filtered or unexported methods }
A Node is an element in the parse tree. The interface is trivial. The interface contains an unexported method so that only types local to this package can satisfy it.
type NodeType ¶
type NodeType int
NodeType identifies the type of a parse tree node.
const ( NodeText NodeType = iota // Plain text. NodeAction // A non-control action such as a field evaluation. NodeBool // A boolean constant. NodeChain // A sequence of field accesses. NodeCommand // An element of a pipeline. NodeDot // The cursor, dot. NodeField // A field or method name. NodeIdentifier // An identifier; always a function name. NodeIf // An if action. NodeList // A list of Nodes. NodeNil // An untyped nil constant. NodeNumber // A numerical constant. NodePipe // A pipeline of commands. NodeRange // A range action. NodeString // A string constant. NodeTemplate // A template invocation action. NodeVariable // A $ variable. NodeWith // A with action. )
type NumberNode ¶
type NumberNode struct { NodeType Pos IsInt bool // Number has an integral value. IsUint bool // Number has an unsigned integral value. IsFloat bool // Number has a floating-point value. IsComplex bool // Number is complex. Int64 int64 // The signed integer value. Uint64 uint64 // The unsigned integer value. Float64 float64 // The floating-point value. Complex128 complex128 // The complex value. Text string // The original textual representation from the input. }
NumberNode holds a number: signed or unsigned integer, float, or complex. The value is parsed and stored under all the types that can represent the value. This simulates in a small amount of code the behavior of Go's ideal constants.
func (*NumberNode) Copy ¶
func (n *NumberNode) Copy() Node
func (*NumberNode) String ¶
func (n *NumberNode) String() string
type PipeNode ¶
type PipeNode struct { NodeType Pos Line int // The line number in the input (deprecated; kept for compatibility) Decl []*VariableNode // Variable declarations in lexical order. Cmds []*CommandNode // The commands in lexical order. }
PipeNode holds a pipeline with optional declaration
type Pos ¶
type Pos int
Pos represents a byte position in the original input text from which this template was parsed.
type RangeNode ¶
type RangeNode struct {
BranchNode
}
RangeNode represents a {{range}} action and its commands.
type StringNode ¶
type StringNode struct { NodeType Pos Quoted string // The original text of the string, with quotes. Text string // The string, after quote processing. }
StringNode holds a string constant. The value has been "unquoted".
func (*StringNode) Copy ¶
func (s *StringNode) Copy() Node
func (*StringNode) String ¶
func (s *StringNode) String() string
type TemplateNode ¶
type TemplateNode struct { NodeType Pos Line int // The line number in the input (deprecated; kept for compatibility) Name string // The name of the template (unquoted). Pipe *PipeNode // The command to evaluate as dot for the template. }
TemplateNode represents a {{template}} action.
func (*TemplateNode) Copy ¶
func (t *TemplateNode) Copy() Node
func (*TemplateNode) String ¶
func (t *TemplateNode) String() string
type Tree ¶
type Tree struct { Name string // name of the template represented by the tree. ParseName string // name of the top-level template during parsing, for error messages. Root *ListNode // top-level root of the tree. // contains filtered or unexported fields }
Tree is the representation of a single parsed template.
func (*Tree) ErrorContext ¶
ErrorContext returns a textual representation of the location of the node in the input text.
func (*Tree) Parse ¶
func (t *Tree) Parse(text, leftDelim, rightDelim string, treeSet map[string]*Tree, funcs ...map[string]interface{}) (tree *Tree, err error)
Parse parses the template definition string to construct a representation of the template for execution. If either action delimiter string is empty, the default ("{{" or "}}") is used. Embedded template definitions are added to the treeSet map.
type VariableNode ¶
type VariableNode struct { NodeType Pos Ident []string // Variable name and fields in lexical order. }
VariableNode holds a list of variable names, possibly with chained field accesses. The dollar sign is part of the (first) name.
func (*VariableNode) Copy ¶
func (v *VariableNode) Copy() Node
func (*VariableNode) String ¶
func (v *VariableNode) String() string