higer <higerinbeij...@gmail.com> wrote: > >My Python version is 2.5.2; When I reading the bytecode of some pyc >file, I always found that there are many jump command from different >position,but to the same position. You can see this situation in >following code(this bytecode is just from one .pyc file and I don't >have its source .py file): >... >From the above bytecode,we know that line 574 is the point that many >position jumps to.So,it just looks like the 'goto' function in C, but >we know that there is none such function in Python. >... >But ,the question is, I have tried a lot of ways(e.g.for loop,while >loop and mixed) to re-present 'goto' style bytecodes like this, but >the result depressed me. >So,I think maybe it is just a compiler optimization in Python2.5? I'm >not sure,so I'm appreciated that if anyone can help me.
I can't figure out what you're asking here. Are you annoyed that the byte code contains GOTOs? This is a silly thing to worry about. The whole purpose of a compiler is to translate a program express in high-level constructs into a lower-level and more primitive format. The simplest form of an "if" statement or a "while" statement always includes unconditional branches. This exact same thing happens with every compiler. Assembly languages, for example, do not have "if/then/else" instructions, nor "while" instructions, nor "switch" instructions. If you write a C program with an "if" statement, the resulting assembly program will contain a "goto" (usually called "jump" or "branch"). Don't worry about it. -- Tim Roberts, t...@probo.com Providenza & Boekelheide, Inc. -- http://mail.python.org/mailman/listinfo/python-list
