diff options
author | Tianon Gravi <admwiggin@gmail.com> | 2015-01-15 11:54:00 -0700 |
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committer | Tianon Gravi <admwiggin@gmail.com> | 2015-01-15 11:54:00 -0700 |
commit | f154da9e12608589e8d5f0508f908a0c3e88a1bb (patch) | |
tree | f8255d51e10c6f1e0ed69702200b966c9556a431 /src/pkg/text/template/parse/node.go | |
parent | 8d8329ed5dfb9622c82a9fbec6fd99a580f9c9f6 (diff) | |
download | golang-upstream/1.4.tar.gz |
Imported Upstream version 1.4upstream/1.4
Diffstat (limited to 'src/pkg/text/template/parse/node.go')
-rw-r--r-- | src/pkg/text/template/parse/node.go | 722 |
1 files changed, 0 insertions, 722 deletions
diff --git a/src/pkg/text/template/parse/node.go b/src/pkg/text/template/parse/node.go deleted file mode 100644 index dc6a3bb92..000000000 --- a/src/pkg/text/template/parse/node.go +++ /dev/null @@ -1,722 +0,0 @@ -// Copyright 2011 The Go Authors. All rights reserved. -// Use of this source code is governed by a BSD-style -// license that can be found in the LICENSE file. - -// Parse nodes. - -package parse - -import ( - "bytes" - "fmt" - "strconv" - "strings" -) - -var textFormat = "%s" // Changed to "%q" in tests for better error messages. - -// 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 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 - // Make sure only functions in this package can create Nodes. - unexported() -} - -// NodeType identifies the type of a parse tree node. -type NodeType int - -// Pos represents a byte position in the original input text from which -// this template was parsed. -type Pos int - -func (p Pos) Position() Pos { - return p -} - -// unexported keeps Node implementations local to the package. -// All implementations embed Pos, so this takes care of it. -func (Pos) unexported() { -} - -// Type returns itself and provides an easy default implementation -// for embedding in a Node. Embedded in all non-trivial Nodes. -func (t NodeType) Type() NodeType { - return t -} - -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. - nodeElse // An else action. Not added to tree. - nodeEnd // An end action. Not added to tree. - 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. -) - -// Nodes. - -// ListNode holds a sequence of nodes. -type ListNode struct { - NodeType - Pos - Nodes []Node // The element nodes in lexical order. -} - -func newList(pos Pos) *ListNode { - return &ListNode{NodeType: NodeList, Pos: pos} -} - -func (l *ListNode) append(n Node) { - l.Nodes = append(l.Nodes, n) -} - -func (l *ListNode) String() string { - b := new(bytes.Buffer) - for _, n := range l.Nodes { - fmt.Fprint(b, n) - } - return b.String() -} - -func (l *ListNode) CopyList() *ListNode { - if l == nil { - return l - } - n := newList(l.Pos) - for _, elem := range l.Nodes { - n.append(elem.Copy()) - } - return n -} - -func (l *ListNode) Copy() Node { - return l.CopyList() -} - -// TextNode holds plain text. -type TextNode struct { - NodeType - Pos - Text []byte // The text; may span newlines. -} - -func newText(pos Pos, text string) *TextNode { - return &TextNode{NodeType: NodeText, Pos: pos, Text: []byte(text)} -} - -func (t *TextNode) String() string { - return fmt.Sprintf(textFormat, t.Text) -} - -func (t *TextNode) Copy() Node { - return &TextNode{NodeType: NodeText, Text: append([]byte{}, t.Text...)} -} - -// PipeNode holds a pipeline with optional declaration -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. -} - -func newPipeline(pos Pos, line int, decl []*VariableNode) *PipeNode { - return &PipeNode{NodeType: NodePipe, Pos: pos, Line: line, Decl: decl} -} - -func (p *PipeNode) append(command *CommandNode) { - p.Cmds = append(p.Cmds, command) -} - -func (p *PipeNode) String() string { - s := "" - if len(p.Decl) > 0 { - for i, v := range p.Decl { - if i > 0 { - s += ", " - } - s += v.String() - } - s += " := " - } - for i, c := range p.Cmds { - if i > 0 { - s += " | " - } - s += c.String() - } - return s -} - -func (p *PipeNode) CopyPipe() *PipeNode { - if p == nil { - return p - } - var decl []*VariableNode - for _, d := range p.Decl { - decl = append(decl, d.Copy().(*VariableNode)) - } - n := newPipeline(p.Pos, p.Line, decl) - for _, c := range p.Cmds { - n.append(c.Copy().(*CommandNode)) - } - return n -} - -func (p *PipeNode) Copy() Node { - return p.CopyPipe() -} - -// 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. -type ActionNode struct { - NodeType - Pos - Line int // The line number in the input (deprecated; kept for compatibility) - Pipe *PipeNode // The pipeline in the action. -} - -func newAction(pos Pos, line int, pipe *PipeNode) *ActionNode { - return &ActionNode{NodeType: NodeAction, Pos: pos, Line: line, Pipe: pipe} -} - -func (a *ActionNode) String() string { - return fmt.Sprintf("{{%s}}", a.Pipe) - -} - -func (a *ActionNode) Copy() Node { - return newAction(a.Pos, a.Line, a.Pipe.CopyPipe()) - -} - -// CommandNode holds a command (a pipeline inside an evaluating action). -type CommandNode struct { - NodeType - Pos - Args []Node // Arguments in lexical order: Identifier, field, or constant. -} - -func newCommand(pos Pos) *CommandNode { - return &CommandNode{NodeType: NodeCommand, Pos: pos} -} - -func (c *CommandNode) append(arg Node) { - c.Args = append(c.Args, arg) -} - -func (c *CommandNode) String() string { - s := "" - for i, arg := range c.Args { - if i > 0 { - s += " " - } - if arg, ok := arg.(*PipeNode); ok { - s += "(" + arg.String() + ")" - continue - } - s += arg.String() - } - return s -} - -func (c *CommandNode) Copy() Node { - if c == nil { - return c - } - n := newCommand(c.Pos) - for _, c := range c.Args { - n.append(c.Copy()) - } - return n -} - -// IdentifierNode holds an identifier. -type IdentifierNode struct { - NodeType - Pos - Ident string // The identifier's name. -} - -// NewIdentifier returns a new IdentifierNode with the given identifier name. -func NewIdentifier(ident string) *IdentifierNode { - return &IdentifierNode{NodeType: NodeIdentifier, Ident: ident} -} - -// SetPos sets the position. NewIdentifier is a public method so we can't modify its signature. -// Chained for convenience. -// TODO: fix one day? -func (i *IdentifierNode) SetPos(pos Pos) *IdentifierNode { - i.Pos = pos - return i -} - -func (i *IdentifierNode) String() string { - return i.Ident -} - -func (i *IdentifierNode) Copy() Node { - return NewIdentifier(i.Ident).SetPos(i.Pos) -} - -// VariableNode holds a list of variable names, possibly with chained field -// accesses. The dollar sign is part of the (first) name. -type VariableNode struct { - NodeType - Pos - Ident []string // Variable name and fields in lexical order. -} - -func newVariable(pos Pos, ident string) *VariableNode { - return &VariableNode{NodeType: NodeVariable, Pos: pos, Ident: strings.Split(ident, ".")} -} - -func (v *VariableNode) String() string { - s := "" - for i, id := range v.Ident { - if i > 0 { - s += "." - } - s += id - } - return s -} - -func (v *VariableNode) Copy() Node { - return &VariableNode{NodeType: NodeVariable, Pos: v.Pos, Ident: append([]string{}, v.Ident...)} -} - -// DotNode holds the special identifier '.'. -type DotNode struct { - Pos -} - -func newDot(pos Pos) *DotNode { - return &DotNode{Pos: pos} -} - -func (d *DotNode) Type() NodeType { - return NodeDot -} - -func (d *DotNode) String() string { - return "." -} - -func (d *DotNode) Copy() Node { - return newDot(d.Pos) -} - -// NilNode holds the special identifier 'nil' representing an untyped nil constant. -type NilNode struct { - Pos -} - -func newNil(pos Pos) *NilNode { - return &NilNode{Pos: pos} -} - -func (n *NilNode) Type() NodeType { - return NodeNil -} - -func (n *NilNode) String() string { - return "nil" -} - -func (n *NilNode) Copy() Node { - return newNil(n.Pos) -} - -// FieldNode holds a field (identifier starting with '.'). -// The names may be chained ('.x.y'). -// The period is dropped from each ident. -type FieldNode struct { - NodeType - Pos - Ident []string // The identifiers in lexical order. -} - -func newField(pos Pos, ident string) *FieldNode { - return &FieldNode{NodeType: NodeField, Pos: pos, Ident: strings.Split(ident[1:], ".")} // [1:] to drop leading period -} - -func (f *FieldNode) String() string { - s := "" - for _, id := range f.Ident { - s += "." + id - } - return s -} - -func (f *FieldNode) Copy() Node { - return &FieldNode{NodeType: NodeField, Pos: f.Pos, Ident: append([]string{}, f.Ident...)} -} - -// 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 ChainNode struct { - NodeType - Pos - Node Node - Field []string // The identifiers in lexical order. -} - -func newChain(pos Pos, node Node) *ChainNode { - return &ChainNode{NodeType: NodeChain, Pos: pos, Node: node} -} - -// Add adds the named field (which should start with a period) to the end of the chain. -func (c *ChainNode) Add(field string) { - if len(field) == 0 || field[0] != '.' { - panic("no dot in field") - } - field = field[1:] // Remove leading dot. - if field == "" { - panic("empty field") - } - c.Field = append(c.Field, field) -} - -func (c *ChainNode) String() string { - s := c.Node.String() - if _, ok := c.Node.(*PipeNode); ok { - s = "(" + s + ")" - } - for _, field := range c.Field { - s += "." + field - } - return s -} - -func (c *ChainNode) Copy() Node { - return &ChainNode{NodeType: NodeChain, Pos: c.Pos, Node: c.Node, Field: append([]string{}, c.Field...)} -} - -// BoolNode holds a boolean constant. -type BoolNode struct { - NodeType - Pos - True bool // The value of the boolean constant. -} - -func newBool(pos Pos, true bool) *BoolNode { - return &BoolNode{NodeType: NodeBool, Pos: pos, True: true} -} - -func (b *BoolNode) String() string { - if b.True { - return "true" - } - return "false" -} - -func (b *BoolNode) Copy() Node { - return newBool(b.Pos, b.True) -} - -// 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. -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. -} - -func newNumber(pos Pos, text string, typ itemType) (*NumberNode, error) { - n := &NumberNode{NodeType: NodeNumber, Pos: pos, Text: text} - switch typ { - case itemCharConstant: - rune, _, tail, err := strconv.UnquoteChar(text[1:], text[0]) - if err != nil { - return nil, err - } - if tail != "'" { - return nil, fmt.Errorf("malformed character constant: %s", text) - } - n.Int64 = int64(rune) - n.IsInt = true - n.Uint64 = uint64(rune) - n.IsUint = true - n.Float64 = float64(rune) // odd but those are the rules. - n.IsFloat = true - return n, nil - case itemComplex: - // fmt.Sscan can parse the pair, so let it do the work. - if _, err := fmt.Sscan(text, &n.Complex128); err != nil { - return nil, err - } - n.IsComplex = true - n.simplifyComplex() - return n, nil - } - // Imaginary constants can only be complex unless they are zero. - if len(text) > 0 && text[len(text)-1] == 'i' { - f, err := strconv.ParseFloat(text[:len(text)-1], 64) - if err == nil { - n.IsComplex = true - n.Complex128 = complex(0, f) - n.simplifyComplex() - return n, nil - } - } - // Do integer test first so we get 0x123 etc. - u, err := strconv.ParseUint(text, 0, 64) // will fail for -0; fixed below. - if err == nil { - n.IsUint = true - n.Uint64 = u - } - i, err := strconv.ParseInt(text, 0, 64) - if err == nil { - n.IsInt = true - n.Int64 = i - if i == 0 { - n.IsUint = true // in case of -0. - n.Uint64 = u - } - } - // If an integer extraction succeeded, promote the float. - if n.IsInt { - n.IsFloat = true - n.Float64 = float64(n.Int64) - } else if n.IsUint { - n.IsFloat = true - n.Float64 = float64(n.Uint64) - } else { - f, err := strconv.ParseFloat(text, 64) - if err == nil { - n.IsFloat = true - n.Float64 = f - // If a floating-point extraction succeeded, extract the int if needed. - if !n.IsInt && float64(int64(f)) == f { - n.IsInt = true - n.Int64 = int64(f) - } - if !n.IsUint && float64(uint64(f)) == f { - n.IsUint = true - n.Uint64 = uint64(f) - } - } - } - if !n.IsInt && !n.IsUint && !n.IsFloat { - return nil, fmt.Errorf("illegal number syntax: %q", text) - } - return n, nil -} - -// simplifyComplex pulls out any other types that are represented by the complex number. -// These all require that the imaginary part be zero. -func (n *NumberNode) simplifyComplex() { - n.IsFloat = imag(n.Complex128) == 0 - if n.IsFloat { - n.Float64 = real(n.Complex128) - n.IsInt = float64(int64(n.Float64)) == n.Float64 - if n.IsInt { - n.Int64 = int64(n.Float64) - } - n.IsUint = float64(uint64(n.Float64)) == n.Float64 - if n.IsUint { - n.Uint64 = uint64(n.Float64) - } - } -} - -func (n *NumberNode) String() string { - return n.Text -} - -func (n *NumberNode) Copy() Node { - nn := new(NumberNode) - *nn = *n // Easy, fast, correct. - return nn -} - -// StringNode holds a string constant. The value has been "unquoted". -type StringNode struct { - NodeType - Pos - Quoted string // The original text of the string, with quotes. - Text string // The string, after quote processing. -} - -func newString(pos Pos, orig, text string) *StringNode { - return &StringNode{NodeType: NodeString, Pos: pos, Quoted: orig, Text: text} -} - -func (s *StringNode) String() string { - return s.Quoted -} - -func (s *StringNode) Copy() Node { - return newString(s.Pos, s.Quoted, s.Text) -} - -// endNode represents an {{end}} action. -// It does not appear in the final parse tree. -type endNode struct { - Pos -} - -func newEnd(pos Pos) *endNode { - return &endNode{Pos: pos} -} - -func (e *endNode) Type() NodeType { - return nodeEnd -} - -func (e *endNode) String() string { - return "{{end}}" -} - -func (e *endNode) Copy() Node { - return newEnd(e.Pos) -} - -// elseNode represents an {{else}} action. Does not appear in the final tree. -type elseNode struct { - NodeType - Pos - Line int // The line number in the input (deprecated; kept for compatibility) -} - -func newElse(pos Pos, line int) *elseNode { - return &elseNode{NodeType: nodeElse, Pos: pos, Line: line} -} - -func (e *elseNode) Type() NodeType { - return nodeElse -} - -func (e *elseNode) String() string { - return "{{else}}" -} - -func (e *elseNode) Copy() Node { - return newElse(e.Pos, e.Line) -} - -// BranchNode is the common representation of if, range, and with. -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). -} - -func (b *BranchNode) String() string { - name := "" - switch b.NodeType { - case NodeIf: - name = "if" - case NodeRange: - name = "range" - case NodeWith: - name = "with" - default: - panic("unknown branch type") - } - if b.ElseList != nil { - return fmt.Sprintf("{{%s %s}}%s{{else}}%s{{end}}", name, b.Pipe, b.List, b.ElseList) - } - return fmt.Sprintf("{{%s %s}}%s{{end}}", name, b.Pipe, b.List) -} - -// IfNode represents an {{if}} action and its commands. -type IfNode struct { - BranchNode -} - -func newIf(pos Pos, line int, pipe *PipeNode, list, elseList *ListNode) *IfNode { - return &IfNode{BranchNode{NodeType: NodeIf, Pos: pos, Line: line, Pipe: pipe, List: list, ElseList: elseList}} -} - -func (i *IfNode) Copy() Node { - return newIf(i.Pos, i.Line, i.Pipe.CopyPipe(), i.List.CopyList(), i.ElseList.CopyList()) -} - -// RangeNode represents a {{range}} action and its commands. -type RangeNode struct { - BranchNode -} - -func newRange(pos Pos, line int, pipe *PipeNode, list, elseList *ListNode) *RangeNode { - return &RangeNode{BranchNode{NodeType: NodeRange, Pos: pos, Line: line, Pipe: pipe, List: list, ElseList: elseList}} -} - -func (r *RangeNode) Copy() Node { - return newRange(r.Pos, r.Line, r.Pipe.CopyPipe(), r.List.CopyList(), r.ElseList.CopyList()) -} - -// WithNode represents a {{with}} action and its commands. -type WithNode struct { - BranchNode -} - -func newWith(pos Pos, line int, pipe *PipeNode, list, elseList *ListNode) *WithNode { - return &WithNode{BranchNode{NodeType: NodeWith, Pos: pos, Line: line, Pipe: pipe, List: list, ElseList: elseList}} -} - -func (w *WithNode) Copy() Node { - return newWith(w.Pos, w.Line, w.Pipe.CopyPipe(), w.List.CopyList(), w.ElseList.CopyList()) -} - -// TemplateNode represents a {{template}} action. -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. -} - -func newTemplate(pos Pos, line int, name string, pipe *PipeNode) *TemplateNode { - return &TemplateNode{NodeType: NodeTemplate, Line: line, Pos: pos, Name: name, Pipe: pipe} -} - -func (t *TemplateNode) String() string { - if t.Pipe == nil { - return fmt.Sprintf("{{template %q}}", t.Name) - } - return fmt.Sprintf("{{template %q %s}}", t.Name, t.Pipe) -} - -func (t *TemplateNode) Copy() Node { - return newTemplate(t.Pos, t.Line, t.Name, t.Pipe.CopyPipe()) -} |