from typedef import *

SIZE_LIST = struct([ (DWORD, 'alignment'), (WORD[4], 'sizes') # array of 4 words ]) VERSION = struct([ (DWORD, 'build_version'), (WORD, 'major'), (WORD, 'minor') ])

FLAGS = union([ (BYTE[4], 'bytes'), (DWORD, 'dw') ])

HEADER = struct([ (VERSION, 'file_version'), # using existing definitions (FLAGS, 'flags'), struct([ (WORD, 'size'), (WORD, 'offset') ], 'inner_struct'), # define nested definitions struct([ (DWORD, 'checksum'), (DWORD, 'machine') ]) # define anonymous nested definitions ])

with pragma.pack(1): # using context manager  # define structs here... ...

pragma.pack.push(4) # explicitly pushing and popping # define structs here... ... pragma.pack.pop() 

ver = VERSION() # using default values for each type

buffer = '\xbb\x01\x02\x03' # using string buffer (`bytes` on py3) ver = VERSION(buffer) 

iobuffer = StringIO('\xbb\x01\x02\x03') # using `StringIO` (`BytesIO` on py3) ver = VERSION(iobuffer) 

in_file = open('{some_path}','rb') # using files ver = VERSION(in_file) 

data_dict = { 'build_version': 9600, 'major': 8, 'minor':1 } # using dictionary for structs ver = VERSION(data_dict) 

data_list = ['\x01\x02', 3, 5] # using list for arrays size_list = SIZE_LIST({'sizes':data_list}) 

if ver.major > 3: ...

for name, value in ver: # iterating over struct/union instance ...

for index, value in size_list.sizes: # iterating over array instance ...

wanted_sizes = size_list.sizes[2:3] # getting slice of array instance ...

>>> ver.minor = 3 >>> ver 00 00 00 00 00 00 03 00 ...

>>> ver.major = '\x01\xFF' >>> ver 00 00 00 00 01 ff 03 00 ...

size_list.sizes = [1,2] ...

# file must have read/write access, and contain enough buffer to initialize the type in_file = open('{some_path}','r+b') ver = VERSION(in_file,mode=F_SYNC) 

>>> bytes(ver) b'\x00\x00\x00\x00\x01\xff\x03\x00'

ARCH_DEP = struct([ (SIZE_T, 'size'), (PVOID, 'pointer') ]) >>> s_32bit = ARCH_DEP('\x00\x00\x00\x00\xFF\xFF\xFF\xFF', target=Arch.x86) >>> s_64bit = ARCH_DEP('\x00\x00\x00\x00\x00\x00\x00\x00\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF', target=Arch.x64) >>> s_32bit.size 0 >>> hex(s_32bit.pointer) '0xffffffff' >>> s_64bit.size 0 >>> hex(s_64bit.pointer) '0xffffffffffffffff' 

 U = union([ (DWORD, 'unsignedLittle'), (~DWORD, 'signedLittle'), (+DWORD, 'unsignedBig'), (+~DWORD, 'signedBig') ])

>>> sizeof(ver) 8