818 lines
15 KiB
Go
818 lines
15 KiB
Go
package dbus
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import (
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"bytes"
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"errors"
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"fmt"
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"io"
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"reflect"
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"strconv"
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"strings"
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"unicode/utf8"
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)
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type varParser struct {
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tokens []varToken
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i int
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}
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func (p *varParser) backup() {
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p.i--
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}
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func (p *varParser) next() varToken {
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if p.i < len(p.tokens) {
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t := p.tokens[p.i]
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p.i++
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return t
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}
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return varToken{typ: tokEOF}
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}
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type varNode interface {
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Infer() (Signature, error)
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String() string
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Sigs() sigSet
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Value(Signature) (interface{}, error)
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}
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func varMakeNode(p *varParser) (varNode, error) {
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var sig Signature
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for {
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t := p.next()
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switch t.typ {
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case tokEOF:
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return nil, io.ErrUnexpectedEOF
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case tokError:
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return nil, errors.New(t.val)
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case tokNumber:
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return varMakeNumNode(t, sig)
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case tokString:
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return varMakeStringNode(t, sig)
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case tokBool:
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if sig.str != "" && sig.str != "b" {
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return nil, varTypeError{t.val, sig}
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}
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b, err := strconv.ParseBool(t.val)
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if err != nil {
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return nil, err
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}
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return boolNode(b), nil
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case tokArrayStart:
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return varMakeArrayNode(p, sig)
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case tokVariantStart:
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return varMakeVariantNode(p, sig)
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case tokDictStart:
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return varMakeDictNode(p, sig)
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case tokType:
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if sig.str != "" {
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return nil, errors.New("unexpected type annotation")
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}
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if t.val[0] == '@' {
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sig.str = t.val[1:]
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} else {
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sig.str = varTypeMap[t.val]
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}
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case tokByteString:
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if sig.str != "" && sig.str != "ay" {
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return nil, varTypeError{t.val, sig}
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}
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b, err := varParseByteString(t.val)
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if err != nil {
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return nil, err
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}
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return byteStringNode(b), nil
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default:
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return nil, fmt.Errorf("unexpected %q", t.val)
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}
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}
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}
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type varTypeError struct {
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val string
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sig Signature
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}
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func (e varTypeError) Error() string {
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return fmt.Sprintf("dbus: can't parse %q as type %q", e.val, e.sig.str)
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}
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type sigSet map[Signature]bool
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func (s sigSet) Empty() bool {
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return len(s) == 0
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}
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func (s sigSet) Intersect(s2 sigSet) sigSet {
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r := make(sigSet)
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for k := range s {
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if s2[k] {
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r[k] = true
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}
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}
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return r
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}
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func (s sigSet) Single() (Signature, bool) {
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if len(s) == 1 {
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for k := range s {
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return k, true
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}
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}
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return Signature{}, false
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}
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func (s sigSet) ToArray() sigSet {
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r := make(sigSet, len(s))
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for k := range s {
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r[Signature{"a" + k.str}] = true
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}
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return r
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}
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type numNode struct {
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sig Signature
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str string
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val interface{}
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}
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var numSigSet = sigSet{
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Signature{"y"}: true,
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Signature{"n"}: true,
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Signature{"q"}: true,
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Signature{"i"}: true,
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Signature{"u"}: true,
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Signature{"x"}: true,
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Signature{"t"}: true,
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Signature{"d"}: true,
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}
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func (n numNode) Infer() (Signature, error) {
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if strings.ContainsAny(n.str, ".e") {
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return Signature{"d"}, nil
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}
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return Signature{"i"}, nil
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}
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func (n numNode) String() string {
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return n.str
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}
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func (n numNode) Sigs() sigSet {
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if n.sig.str != "" {
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return sigSet{n.sig: true}
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}
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if strings.ContainsAny(n.str, ".e") {
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return sigSet{Signature{"d"}: true}
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}
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return numSigSet
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}
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func (n numNode) Value(sig Signature) (interface{}, error) {
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if n.sig.str != "" && n.sig != sig {
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return nil, varTypeError{n.str, sig}
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}
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if n.val != nil {
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return n.val, nil
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}
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return varNumAs(n.str, sig)
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}
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func varMakeNumNode(tok varToken, sig Signature) (varNode, error) {
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if sig.str == "" {
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return numNode{str: tok.val}, nil
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}
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num, err := varNumAs(tok.val, sig)
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if err != nil {
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return nil, err
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}
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return numNode{sig: sig, val: num}, nil
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}
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func varNumAs(s string, sig Signature) (interface{}, error) {
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isUnsigned := false
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size := 32
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switch sig.str {
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case "n":
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size = 16
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case "i":
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case "x":
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size = 64
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case "y":
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size = 8
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isUnsigned = true
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case "q":
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size = 16
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isUnsigned = true
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case "u":
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isUnsigned = true
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case "t":
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size = 64
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isUnsigned = true
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case "d":
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d, err := strconv.ParseFloat(s, 64)
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if err != nil {
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return nil, err
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}
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return d, nil
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default:
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return nil, varTypeError{s, sig}
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}
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base := 10
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if strings.HasPrefix(s, "0x") {
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base = 16
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s = s[2:]
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}
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if strings.HasPrefix(s, "0") && len(s) != 1 {
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base = 8
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s = s[1:]
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}
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if isUnsigned {
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i, err := strconv.ParseUint(s, base, size)
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if err != nil {
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return nil, err
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}
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var v interface{} = i
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switch sig.str {
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case "y":
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v = byte(i)
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case "q":
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v = uint16(i)
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case "u":
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v = uint32(i)
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}
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return v, nil
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}
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i, err := strconv.ParseInt(s, base, size)
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if err != nil {
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return nil, err
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}
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var v interface{} = i
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switch sig.str {
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case "n":
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v = int16(i)
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case "i":
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v = int32(i)
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}
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return v, nil
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}
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type stringNode struct {
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sig Signature
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str string // parsed
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val interface{} // has correct type
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}
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var stringSigSet = sigSet{
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Signature{"s"}: true,
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Signature{"g"}: true,
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Signature{"o"}: true,
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}
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func (n stringNode) Infer() (Signature, error) {
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return Signature{"s"}, nil
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}
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func (n stringNode) String() string {
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return n.str
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}
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func (n stringNode) Sigs() sigSet {
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if n.sig.str != "" {
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return sigSet{n.sig: true}
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}
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return stringSigSet
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}
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func (n stringNode) Value(sig Signature) (interface{}, error) {
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if n.sig.str != "" && n.sig != sig {
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return nil, varTypeError{n.str, sig}
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}
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if n.val != nil {
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return n.val, nil
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}
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switch {
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case sig.str == "g":
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return Signature{n.str}, nil
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case sig.str == "o":
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return ObjectPath(n.str), nil
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case sig.str == "s":
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return n.str, nil
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default:
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return nil, varTypeError{n.str, sig}
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}
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}
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func varMakeStringNode(tok varToken, sig Signature) (varNode, error) {
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if sig.str != "" && sig.str != "s" && sig.str != "g" && sig.str != "o" {
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return nil, fmt.Errorf("invalid type %q for string", sig.str)
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}
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s, err := varParseString(tok.val)
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if err != nil {
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return nil, err
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}
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n := stringNode{str: s}
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if sig.str == "" {
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return stringNode{str: s}, nil
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}
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n.sig = sig
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switch sig.str {
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case "o":
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n.val = ObjectPath(s)
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case "g":
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n.val = Signature{s}
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case "s":
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n.val = s
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}
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return n, nil
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}
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func varParseString(s string) (string, error) {
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// quotes are guaranteed to be there
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s = s[1 : len(s)-1]
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buf := new(bytes.Buffer)
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for len(s) != 0 {
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r, size := utf8.DecodeRuneInString(s)
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if r == utf8.RuneError && size == 1 {
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return "", errors.New("invalid UTF-8")
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}
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s = s[size:]
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if r != '\\' {
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buf.WriteRune(r)
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continue
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}
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r, size = utf8.DecodeRuneInString(s)
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if r == utf8.RuneError && size == 1 {
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return "", errors.New("invalid UTF-8")
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}
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s = s[size:]
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switch r {
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case 'a':
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buf.WriteRune(0x7)
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case 'b':
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buf.WriteRune(0x8)
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case 'f':
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buf.WriteRune(0xc)
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case 'n':
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buf.WriteRune('\n')
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case 'r':
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buf.WriteRune('\r')
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case 't':
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buf.WriteRune('\t')
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case '\n':
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case 'u':
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if len(s) < 4 {
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return "", errors.New("short unicode escape")
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}
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r, err := strconv.ParseUint(s[:4], 16, 32)
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if err != nil {
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return "", err
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}
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buf.WriteRune(rune(r))
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s = s[4:]
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case 'U':
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if len(s) < 8 {
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return "", errors.New("short unicode escape")
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}
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r, err := strconv.ParseUint(s[:8], 16, 32)
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if err != nil {
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return "", err
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}
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buf.WriteRune(rune(r))
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s = s[8:]
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default:
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buf.WriteRune(r)
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}
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}
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return buf.String(), nil
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}
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var boolSigSet = sigSet{Signature{"b"}: true}
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type boolNode bool
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func (boolNode) Infer() (Signature, error) {
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return Signature{"b"}, nil
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}
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func (b boolNode) String() string {
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if b {
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return "true"
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}
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return "false"
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}
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func (boolNode) Sigs() sigSet {
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return boolSigSet
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}
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func (b boolNode) Value(sig Signature) (interface{}, error) {
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if sig.str != "b" {
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return nil, varTypeError{b.String(), sig}
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}
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return bool(b), nil
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}
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type arrayNode struct {
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set sigSet
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children []varNode
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val interface{}
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}
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func (n arrayNode) Infer() (Signature, error) {
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for _, v := range n.children {
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csig, err := varInfer(v)
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if err != nil {
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continue
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}
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return Signature{"a" + csig.str}, nil
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}
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return Signature{}, fmt.Errorf("can't infer type for %q", n.String())
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}
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func (n arrayNode) String() string {
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s := "["
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for i, v := range n.children {
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s += v.String()
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if i != len(n.children)-1 {
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s += ", "
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}
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}
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return s + "]"
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}
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func (n arrayNode) Sigs() sigSet {
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return n.set
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}
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func (n arrayNode) Value(sig Signature) (interface{}, error) {
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if n.set.Empty() {
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// no type information whatsoever, so this must be an empty slice
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return reflect.MakeSlice(typeFor(sig.str), 0, 0).Interface(), nil
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}
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if !n.set[sig] {
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return nil, varTypeError{n.String(), sig}
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}
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s := reflect.MakeSlice(typeFor(sig.str), len(n.children), len(n.children))
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for i, v := range n.children {
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rv, err := v.Value(Signature{sig.str[1:]})
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if err != nil {
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return nil, err
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}
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s.Index(i).Set(reflect.ValueOf(rv))
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}
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return s.Interface(), nil
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}
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func varMakeArrayNode(p *varParser, sig Signature) (varNode, error) {
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var n arrayNode
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if sig.str != "" {
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n.set = sigSet{sig: true}
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}
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if t := p.next(); t.typ == tokArrayEnd {
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return n, nil
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} else {
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p.backup()
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}
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Loop:
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for {
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t := p.next()
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switch t.typ {
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case tokEOF:
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return nil, io.ErrUnexpectedEOF
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case tokError:
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return nil, errors.New(t.val)
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}
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p.backup()
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cn, err := varMakeNode(p)
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if err != nil {
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return nil, err
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}
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if cset := cn.Sigs(); !cset.Empty() {
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if n.set.Empty() {
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n.set = cset.ToArray()
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} else {
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nset := cset.ToArray().Intersect(n.set)
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if nset.Empty() {
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return nil, fmt.Errorf("can't parse %q with given type information", cn.String())
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}
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n.set = nset
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}
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}
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n.children = append(n.children, cn)
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switch t := p.next(); t.typ {
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case tokEOF:
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return nil, io.ErrUnexpectedEOF
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case tokError:
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return nil, errors.New(t.val)
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case tokArrayEnd:
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break Loop
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case tokComma:
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continue
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default:
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return nil, fmt.Errorf("unexpected %q", t.val)
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}
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}
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return n, nil
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}
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type variantNode struct {
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n varNode
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}
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var variantSet = sigSet{
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Signature{"v"}: true,
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}
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func (variantNode) Infer() (Signature, error) {
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return Signature{"v"}, nil
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}
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func (n variantNode) String() string {
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return "<" + n.n.String() + ">"
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}
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func (variantNode) Sigs() sigSet {
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return variantSet
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}
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func (n variantNode) Value(sig Signature) (interface{}, error) {
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if sig.str != "v" {
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return nil, varTypeError{n.String(), sig}
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}
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sig, err := varInfer(n.n)
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if err != nil {
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return nil, err
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}
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v, err := n.n.Value(sig)
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if err != nil {
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return nil, err
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}
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return MakeVariant(v), nil
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}
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func varMakeVariantNode(p *varParser, sig Signature) (varNode, error) {
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n, err := varMakeNode(p)
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if err != nil {
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return nil, err
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}
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if t := p.next(); t.typ != tokVariantEnd {
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return nil, fmt.Errorf("unexpected %q", t.val)
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}
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vn := variantNode{n}
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if sig.str != "" && sig.str != "v" {
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return nil, varTypeError{vn.String(), sig}
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}
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return variantNode{n}, nil
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}
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type dictEntry struct {
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key, val varNode
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}
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type dictNode struct {
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kset, vset sigSet
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children []dictEntry
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val interface{}
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}
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func (n dictNode) Infer() (Signature, error) {
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for _, v := range n.children {
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ksig, err := varInfer(v.key)
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if err != nil {
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continue
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}
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vsig, err := varInfer(v.val)
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if err != nil {
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continue
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}
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return Signature{"a{" + ksig.str + vsig.str + "}"}, nil
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}
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return Signature{}, fmt.Errorf("can't infer type for %q", n.String())
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}
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func (n dictNode) String() string {
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s := "{"
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for i, v := range n.children {
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s += v.key.String() + ": " + v.val.String()
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if i != len(n.children)-1 {
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s += ", "
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}
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}
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|
return s + "}"
|
|
}
|
|
|
|
func (n dictNode) Sigs() sigSet {
|
|
r := sigSet{}
|
|
for k := range n.kset {
|
|
for v := range n.vset {
|
|
sig := "a{" + k.str + v.str + "}"
|
|
r[Signature{sig}] = true
|
|
}
|
|
}
|
|
return r
|
|
}
|
|
|
|
func (n dictNode) Value(sig Signature) (interface{}, error) {
|
|
set := n.Sigs()
|
|
if set.Empty() {
|
|
// no type information -> empty dict
|
|
return reflect.MakeMap(typeFor(sig.str)).Interface(), nil
|
|
}
|
|
if !set[sig] {
|
|
return nil, varTypeError{n.String(), sig}
|
|
}
|
|
m := reflect.MakeMap(typeFor(sig.str))
|
|
ksig := Signature{sig.str[2:3]}
|
|
vsig := Signature{sig.str[3 : len(sig.str)-1]}
|
|
for _, v := range n.children {
|
|
kv, err := v.key.Value(ksig)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
vv, err := v.val.Value(vsig)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
m.SetMapIndex(reflect.ValueOf(kv), reflect.ValueOf(vv))
|
|
}
|
|
return m.Interface(), nil
|
|
}
|
|
|
|
func varMakeDictNode(p *varParser, sig Signature) (varNode, error) {
|
|
var n dictNode
|
|
|
|
if sig.str != "" {
|
|
if len(sig.str) < 5 {
|
|
return nil, fmt.Errorf("invalid signature %q for dict type", sig)
|
|
}
|
|
ksig := Signature{string(sig.str[2])}
|
|
vsig := Signature{sig.str[3 : len(sig.str)-1]}
|
|
n.kset = sigSet{ksig: true}
|
|
n.vset = sigSet{vsig: true}
|
|
}
|
|
if t := p.next(); t.typ == tokDictEnd {
|
|
return n, nil
|
|
} else {
|
|
p.backup()
|
|
}
|
|
Loop:
|
|
for {
|
|
t := p.next()
|
|
switch t.typ {
|
|
case tokEOF:
|
|
return nil, io.ErrUnexpectedEOF
|
|
case tokError:
|
|
return nil, errors.New(t.val)
|
|
}
|
|
p.backup()
|
|
kn, err := varMakeNode(p)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
if kset := kn.Sigs(); !kset.Empty() {
|
|
if n.kset.Empty() {
|
|
n.kset = kset
|
|
} else {
|
|
n.kset = kset.Intersect(n.kset)
|
|
if n.kset.Empty() {
|
|
return nil, fmt.Errorf("can't parse %q with given type information", kn.String())
|
|
}
|
|
}
|
|
}
|
|
t = p.next()
|
|
switch t.typ {
|
|
case tokEOF:
|
|
return nil, io.ErrUnexpectedEOF
|
|
case tokError:
|
|
return nil, errors.New(t.val)
|
|
case tokColon:
|
|
default:
|
|
return nil, fmt.Errorf("unexpected %q", t.val)
|
|
}
|
|
t = p.next()
|
|
switch t.typ {
|
|
case tokEOF:
|
|
return nil, io.ErrUnexpectedEOF
|
|
case tokError:
|
|
return nil, errors.New(t.val)
|
|
}
|
|
p.backup()
|
|
vn, err := varMakeNode(p)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
if vset := vn.Sigs(); !vset.Empty() {
|
|
if n.vset.Empty() {
|
|
n.vset = vset
|
|
} else {
|
|
n.vset = n.vset.Intersect(vset)
|
|
if n.vset.Empty() {
|
|
return nil, fmt.Errorf("can't parse %q with given type information", vn.String())
|
|
}
|
|
}
|
|
}
|
|
n.children = append(n.children, dictEntry{kn, vn})
|
|
t = p.next()
|
|
switch t.typ {
|
|
case tokEOF:
|
|
return nil, io.ErrUnexpectedEOF
|
|
case tokError:
|
|
return nil, errors.New(t.val)
|
|
case tokDictEnd:
|
|
break Loop
|
|
case tokComma:
|
|
continue
|
|
default:
|
|
return nil, fmt.Errorf("unexpected %q", t.val)
|
|
}
|
|
}
|
|
return n, nil
|
|
}
|
|
|
|
type byteStringNode []byte
|
|
|
|
var byteStringSet = sigSet{
|
|
Signature{"ay"}: true,
|
|
}
|
|
|
|
func (byteStringNode) Infer() (Signature, error) {
|
|
return Signature{"ay"}, nil
|
|
}
|
|
|
|
func (b byteStringNode) String() string {
|
|
return string(b)
|
|
}
|
|
|
|
func (b byteStringNode) Sigs() sigSet {
|
|
return byteStringSet
|
|
}
|
|
|
|
func (b byteStringNode) Value(sig Signature) (interface{}, error) {
|
|
if sig.str != "ay" {
|
|
return nil, varTypeError{b.String(), sig}
|
|
}
|
|
return []byte(b), nil
|
|
}
|
|
|
|
func varParseByteString(s string) ([]byte, error) {
|
|
// quotes and b at start are guaranteed to be there
|
|
b := make([]byte, 0, 1)
|
|
s = s[2 : len(s)-1]
|
|
for len(s) != 0 {
|
|
c := s[0]
|
|
s = s[1:]
|
|
if c != '\\' {
|
|
b = append(b, c)
|
|
continue
|
|
}
|
|
c = s[0]
|
|
s = s[1:]
|
|
switch c {
|
|
case 'a':
|
|
b = append(b, 0x7)
|
|
case 'b':
|
|
b = append(b, 0x8)
|
|
case 'f':
|
|
b = append(b, 0xc)
|
|
case 'n':
|
|
b = append(b, '\n')
|
|
case 'r':
|
|
b = append(b, '\r')
|
|
case 't':
|
|
b = append(b, '\t')
|
|
case 'x':
|
|
if len(s) < 2 {
|
|
return nil, errors.New("short escape")
|
|
}
|
|
n, err := strconv.ParseUint(s[:2], 16, 8)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
b = append(b, byte(n))
|
|
s = s[2:]
|
|
case '0':
|
|
if len(s) < 3 {
|
|
return nil, errors.New("short escape")
|
|
}
|
|
n, err := strconv.ParseUint(s[:3], 8, 8)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
b = append(b, byte(n))
|
|
s = s[3:]
|
|
default:
|
|
b = append(b, c)
|
|
}
|
|
}
|
|
return append(b, 0), nil
|
|
}
|
|
|
|
func varInfer(n varNode) (Signature, error) {
|
|
if sig, ok := n.Sigs().Single(); ok {
|
|
return sig, nil
|
|
}
|
|
return n.Infer()
|
|
}
|