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‎.gitignore

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*~

‎marshal/marshal.go

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// Implement unmarshal and marshal
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package marshal
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import (
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"encoding/binary"
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"errors"
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"github.com/ncw/gpython/py"
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"io"
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"strconv"
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"fmt"
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)
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const (
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TYPE_NULL = '0'
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TYPE_NONE = 'N'
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TYPE_FALSE = 'F'
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TYPE_TRUE = 'T'
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TYPE_STOPITER = 'S'
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TYPE_ELLIPSIS = '.'
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TYPE_INT = 'i'
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TYPE_FLOAT = 'f'
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TYPE_BINARY_FLOAT = 'g'
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TYPE_COMPLEX = 'x'
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TYPE_BINARY_COMPLEX = 'y'
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TYPE_LONG = 'l'
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TYPE_STRING = 's'
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TYPE_INTERNED = 't'
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TYPE_REF = 'r'
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TYPE_TUPLE = '('
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TYPE_LIST = '['
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TYPE_DICT = '{'
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TYPE_CODE = 'c'
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TYPE_UNICODE = 'u'
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TYPE_UNKNOWN = '?'
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TYPE_SET = '<'
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TYPE_FROZENSET = '>'
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FLAG_REF = 0x80 // with a type, add obj to index
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SIZE32_MAX = 0x7FFFFFFF
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// We assume that Python ints are stored internally in base some power of
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// 2**15; for the sake of portability we'll always read and write them in base
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// exactly 2**15.
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PyLong_MARSHAL_SHIFT = 15
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PyLong_MARSHAL_BASE = (1 << PyLong_MARSHAL_SHIFT)
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PyLong_MARSHAL_MASK = (PyLong_MARSHAL_BASE - 1)
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)
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// Reads an object from the input
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func ReadObject(r io.Reader) (obj py.Object, err error) {
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var code byte
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err = binary.Read(r, binary.LittleEndian, &code)
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if err != nil {
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return
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}
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//flag := code & FLAG_REF
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Type := code &^ FLAG_REF
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switch Type {
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case TYPE_NULL:
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// A null object
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return nil, nil
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case TYPE_NONE:
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// The Python None object
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return py.None, nil
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case TYPE_FALSE:
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// The python False object
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return py.False, nil
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case TYPE_TRUE:
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// The python True object
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return py.True, nil
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case TYPE_STOPITER:
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// The python StopIteration Exception
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return py.StopIteration, nil
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case TYPE_ELLIPSIS:
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// The python elipsis object
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return py.Elipsis, nil
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case TYPE_INT:
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// 4 bytes of signed integer
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var n int32
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err = binary.Read(r, binary.LittleEndian, &n)
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if err != nil {
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return n, nil
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}
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case TYPE_FLOAT:
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// Floating point number as a string
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var length uint8
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err = binary.Read(r, binary.LittleEndian, &length)
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if err != nil {
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return
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}
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buf := make([]byte, int(length))
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_, err = io.ReadFull(r, buf)
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if err != nil {
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return
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}
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var f float64
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f, err = strconv.ParseFloat(string(buf), 64)
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if err != nil {
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return
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}
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return f, nil
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case TYPE_BINARY_FLOAT:
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var f float64
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err = binary.Read(r, binary.LittleEndian, &f)
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if err != nil {
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return
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}
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return f, nil
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case TYPE_COMPLEX:
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// Complex number as a string
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// FIXME this is using Go conversion not Python conversion which may differ
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var length uint8
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err = binary.Read(r, binary.LittleEndian, &length)
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if err != nil {
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return
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}
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buf := make([]byte, int(length))
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_, err = io.ReadFull(r, buf)
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if err != nil {
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return
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}
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var c complex64
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// FIXME c, err = strconv.ParseComplex(string(buf), 64)
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if err != nil {
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return
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}
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return c, nil
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case TYPE_BINARY_COMPLEX:
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var c complex64
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err = binary.Read(r, binary.LittleEndian, &c)
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if err != nil {
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return
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}
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return c, nil
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case TYPE_LONG:
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var size int32
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err = binary.Read(r, binary.LittleEndian, &size)
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if err != nil {
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return
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}
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// FIXME negative := false
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if size < 0 {
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// FIXME negative = true
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size = -size
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}
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if size < 0 || size > SIZE32_MAX {
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return nil, errors.New("bad marshal data (long size out of range)")
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}
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// FIXME not sure what -ve size means!
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// Now read shorts which have 15 bits of the number in
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digits := make([]int16, size)
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err = binary.Read(r, binary.LittleEndian, &size)
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if err != nil {
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return
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}
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if digits[0] == 0 {
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// FIXME should be ValueError
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return nil, errors.New("bad marshal data (digit out of range in long)")
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}
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// FIXME actually convert into something...
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return digits, nil
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case TYPE_STRING, TYPE_INTERNED, TYPE_UNICODE:
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var size int32
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err = binary.Read(r, binary.LittleEndian, &size)
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if err != nil {
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return
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}
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if size < 0 || size > SIZE32_MAX {
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return nil, errors.New("bad marshal data (string size out of range)")
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}
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buf := make([]byte, int(size))
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_, err = io.ReadFull(r, buf)
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if err != nil {
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return
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}
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// FIXME do something different for unicode & interned?
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return string(buf), nil
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case TYPE_TUPLE, TYPE_LIST, TYPE_SET, TYPE_FROZENSET:
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var size int32
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err = binary.Read(r, binary.LittleEndian, &size)
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if err != nil {
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return
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}
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if size < 0 || size > SIZE32_MAX {
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return nil, errors.New("bad marshal data (tuple size out of range)")
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}
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tuple := make([]py.Object, int(size))
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for i := range tuple {
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tuple[i], err = ReadObject(r)
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if err != nil {
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return
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}
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}
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// FIXME differentiate the types TYPE_TUPLE, TYPE_LIST, TYPE_SET, TYPE_FROZENSET
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return tuple, nil
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case TYPE_DICT:
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dict := make(map[py.Object]py.Object)
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var key, value py.Object
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for {
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key, err = ReadObject(r)
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if err != nil {
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return
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}
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if key == nil {
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break
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}
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value, err = ReadObject(r)
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if err != nil {
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return
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}
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if value != nil {
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dict[key] = value
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}
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}
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return dict, nil
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case TYPE_REF:
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// Reference to something???
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var n int32
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err = binary.Read(r, binary.LittleEndian, &n)
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if err != nil {
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return
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}
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// FIXME
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case TYPE_CODE:
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var argcount int32
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var kwonlyargcount int32
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var nlocals int32
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var stacksize int32
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var flags int32
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var code py.Object
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var consts py.Object
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var names py.Object
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var varnames py.Object
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var freevars py.Object
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var cellvars py.Object
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var filename py.Object
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var name py.Object
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var firstlineno int32
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var lnotab py.Object
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if err = binary.Read(r, binary.LittleEndian, &argcount); err != nil {
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return
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}
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if err = binary.Read(r, binary.LittleEndian, &kwonlyargcount); err != nil {
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return
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}
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if err = binary.Read(r, binary.LittleEndian, &nlocals); err != nil {
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return
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}
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if err = binary.Read(r, binary.LittleEndian, &stacksize); err != nil {
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return
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}
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if err = binary.Read(r, binary.LittleEndian, &flags); err != nil {
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return
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}
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if code, err = ReadObject(r); err != nil {
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return
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}
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if consts, err = ReadObject(r); err != nil {
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return
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}
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if names, err = ReadObject(r); err != nil {
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return
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}
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if varnames, err = ReadObject(r); err != nil {
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return
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}
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if freevars, err = ReadObject(r); err != nil {
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return
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}
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if cellvars, err = ReadObject(r); err != nil {
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return
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}
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if filename, err = ReadObject(r); err != nil {
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return
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}
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if name, err = ReadObject(r); err != nil {
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return
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}
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if err = binary.Read(r, binary.LittleEndian, &firstlineno); err != nil {
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return
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}
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if lnotab, err = ReadObject(r); err != nil {
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return
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}
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fmt.Printf("argcount = %v\n", argcount)
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fmt.Printf("kwonlyargcount = %v\n", kwonlyargcount)
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fmt.Printf("nlocals = %v\n", nlocals)
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fmt.Printf("stacksize = %v\n", stacksize)
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fmt.Printf("flags = %v\n", flags)
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fmt.Printf("code = %v\n", code)
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fmt.Printf("consts = %v\n", consts)
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fmt.Printf("names = %v\n", names)
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fmt.Printf("varnames = %v\n", varnames)
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fmt.Printf("freevars = %v\n", freevars)
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fmt.Printf("cellvars = %v\n", cellvars)
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fmt.Printf("filename = %v\n", filename)
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fmt.Printf("name = %v\n", name)
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fmt.Printf("firstlineno = %v\n", firstlineno)
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fmt.Printf("lnotab = %v\n", lnotab)
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/*
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v = (PyObject *) PyCode_New(
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argcount, kwonlyargcount,
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nlocals, stacksize, flags,
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code, consts, names, varnames,
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freevars, cellvars, filename, name,
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firstlineno, lnotab);
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*/
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return code, nil // FIXME
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default:
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return nil, errors.New("bad marshal data (unknown type code)")
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}
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return
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}

‎py/py.go

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// Python global definitions
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package py
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// A python object
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type Object interface{}
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// Some well known objects
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var (
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None, False, True, StopIteration, Elipsis Object
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)

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