On Thu, 17 Nov 2016 10:37 pm, BartC wrote:
> Try:
>
> import dis
>
> def fn():
> | global x
> | x=10
>
> dis.dis(fn)
>
> (I don't know how to disassemble code outside a function, not from
> inside the same program. Outside it might be: 'python -m dis file.py')
You can use the byte-code compiler to compile the code first:
For an expression, you can use:
code = compile("x + 1", "", "eval")
The middle argument, shown here as an empty string "", is used for an
optional string identifying the source of the code. E.g. a file name.
The third argument, here shown as "eval", determines the compilation mode.
The eval() function can only evaluate a single expression, so the name of
the mode is the same.
For a single statement, as seen by the interactive interpreter, use:
code = compile("result = x + 1", "", "single")
For multiple statements (as in a module), or a single statement *not* in the
interactive interpreter, use:
code = compile("result = x + 1", "", "exec")
code = compile("""
x = 999
result = x + 1
print(result)
""", "", "exec")
Then once you have your code object, you can disassemble it:
dis.dis(code)
or exec/eval it:
exec(code)
eval(code) # only if the compilation mode was "eval"
In the most recent versions of Python, dis.dis() will also accept a string:
py> dis.dis('y = x + 1')
1 0 LOAD_NAME 0 (x)
3 LOAD_CONST 0 (1)
6 BINARY_ADD
7 STORE_NAME 1 (y)
10 LOAD_CONST 1 (None)
13 RETURN_VALUE
--
Steve
“Cheer up,” they said, “things could be worse.” So I cheered up, and sure
enough, things got worse.
--
https://mail.python.org/mailman/listinfo/python-list
