---
tags: comp-decomp
title: Perturbing Rules
---

# Rule 1: Extending Variable

## 1a. Adding methods

Change:

foo

to

foo.bar()

disassmebly:

0    LOAD_NAME
2    LOAD_METHOD
4    CALL_METHOD
6    POP_TOP

### 1a-(i). Adding methods args

Change:

foo.bar()

to

foo.bar(arg)

disassmebly:

0    LOAD_NAME
2    LOAD_METHOD
4    LOAD_NAME
6    CALL_METHOD
8    POP_TOP

## 1b. Adding attribute

Change:

foo

to

foo.bar

disassmebly:

0 LOAD_NAME               27 (sys)
2 LOAD_ATTR               28 (platform)

## 1c. Storing variable

Change:

foo

to

bar = foo

disassmebly:

0 LOAD_NAME               
2 STORE_NAME             

## 1d. Converting to function
Change:

foo

to

foo()

disassmebly:

0 LOAD_NAME               
2 CALL_FUNCTION
4 POP_TOP

### 1d-(i). Adding arguments

Change:

foo()

to

foo(arg)

disassmebly:

0 LOAD_NAME 
2 LOAD_NAME 
4 CALL_FUNCTION
6 POP_TOP

### 1d-(ii). Removing arguments

Change:

foo(arg)

to

foo()

disassmebly:

2 LOAD_NAME 
4 CALL_FUNCTION
6 POP_TOP

## 1e. Removing methods

Change:

foo.bar()

to

foo

disassmebly:

0    LOAD_NAME
2    POP_TOP

# Rule 2: Extending Tuple

## 2a. Adding to tuple
Change:

(foo)

to

(foo, bar)

disassmebly:

0 LOAD_NAME   
2 LOAD_NAME
4 BUILD_TUPLE             

# Rule 3: Exception blocks

## 3a. Creating Exception block:
Change:

to

try:
    pass
except:
    pass

## 3b. Changing Exception type:
Change

except:

to

except TypeError:

disassembly:

 68 DUP_TOP
 70 LOAD_NAME               14 (Exception)
 72 COMPARE_OP              10 (exception match)
 74 POP_JUMP_IF_FALSE       94
 76 POP_TOP
 78 POP_TOP
 80 POP_TOP

# Rule 4: Converting imports

## 4a. Adding `import *`
Change

import ctypes

to

from ctypes import *

disassembly:

0 LOAD_CONST               0 (0)
2 LOAD_CONST               1 (('*',))
4 IMPORT_NAME              0 (ctypes)
6 IMPORT_STAR