另一位Python新手试图移植到C / C ++问题。 [英] Another Python rookie trying to port to C/C++ question.

问题描述

一两个星期前，我在这里问到有关将Python移植到C的问题。得到了一些好的

答案（注1）但现在我又得到了另一个题。实际上，更多的请求澄清一个主题，Python教程和

文档给我的理解留下了一丝阴影。


词典/词典类型......


当我认为

" dict"时，我是否理解/正确理解？变量可以看作（有效）两个并行数组吗？

像这样的C构造：


struct DictStruct

{

char * KeyArray [< somenumber>];

ValType ValArray [< somenumber>];

}


其中ValType可能是一个联盟，允许

正确地分配/检索实际值取决于他们的个人类型是什么，以及< somenumber>就是这样：一些

或多或少的任意选择值，提供足够的空间来处理所有预期数量的键/值对？


同样，类似于：


struct DictStruct

{

char Key [25];

ValType值;

DictStruct * PrevDictEntry;

DictStruct * NextDictEntry;

}

（同样，ValType可能是一个联盟，涵盖了字典中可能需要的每种类型的值

- 但在这种情况下，Key直接

包含Key的名称，然后构建一个双链接结构列表

DictStructs最终表现得至少像Python一样dict？


我希望其中任何一个都是Python

处理dicts的合理传真，当然还有相应的开销（可能很少，我可能很少，我我在想......但我还没有编写那部分代码，

所以我可能会发现这将是一场噩梦）我们希望价值

与关键一致，所以我们有走到KeyArray []直到我们找到一个

匹配，然后从另一个数组中提取值，或者为双向链表列出类似的

过程。


或者我在离开场地的方式我是RTFM吗？


（注1）

除了相当多的完全不受欢迎的Python传福音之外。 -

与C / C ++或任何其他语言相比，我不在乎Python有多好，坏或无关紧要的部分是什么？b $ b。我希望这个Python代码是用C / C ++编写的b $ b，讨论结束。对于那些自己接受传教的人来说是不够清楚的（包括那个因为b $ b决定吐出相对令人印象深刻的白痴（就像这样的事情一样）一串侮辱我是多么愚蠢，我的屁股到底有多远，以及如何可怜我的家人一直回到亚当必须是为了制作这样的一个

的回归，因为我没有兴趣采用完美的

语言......）来看看我的Python优点和$ / b $ b in-mailbox？


-

Don Bruder - da **** @ sonic.net < ---首选电子邮件 - SpamAssassinated。

仇恨垃圾邮件？见< http：//www.spamassassin.org>对于一些非常好的信息。

我会选择一条清晰的道路：我会选择自由意志！ - N. Peart

飞行陷阱信息页面：< http://www.sonic.net/~dakidd/Horses/FlyTrap/index.html>

A week or two ago, I asked here about porting Python to C. Got some good
answers (Note 1) but now I''ve got another question. Actually, more a
request for clarification of a topic that both the Python tutorial and
docs leave a touch murky to my understanding.

Dictionaries/"dict" types...

Am I understanding/interpreting correctly when I go with the idea that a
"dict" variable can be looked at as (effectively) two parallel arrays?
Something like this C construct:

struct DictStruct
{
char *KeyArray[<somenumber>];
ValType ValArray[<somenumber>];
}

Where "ValType" would be likely be a union, to allow
assigning/retrieving the actual values correctly depending on what their
individiual types were, and "<somenumber>" is just that: Some
more-or-less arbitrarily selected value that provides enough space to
handle all expected numbers of key/value pairs?

Similarly, would something like:

struct DictStruct
{
char Key[25];
ValType Value;
DictStruct *PrevDictEntry;
DictStruct *NextDictEntry;
}

(again, ValType would probably be a union to cover each type of value
that might be wanted in the dictionary - but in this case, Key directly
contains the Key''s name) then building a double-linked list of struct
DictStructs end up behaving at least reasonably like a Python "dict"?

I expect that either will be a reasonable facsimile of how Python
handles dicts, with, of course, the corresponding overhead (which may be
surprisingly little, I''m thinking... but I have yet to code that part,
so I may find out it''s going to be a nightmare) of "We want the value
that goes with key, so we''ve got to walk the KeyArray[] until we find a
match, then extract the value from the other array", or a similar
procedure for the doubly-linked list.

Or am I way out in left field with the way I''m RTFM?

(Note 1)
Along with quite a bit of entirely unwelcome "Python evangelism" --
Which part of "I don''t care how good, bad, or indifferent Python is
compared to C/C++, or any other language. I want this Python code to be
written in C/C++, end of discussion." wasn''t clear enough for those of
you who took it upon yourselves to preach (including the idiot who
decided to spew a relatively impressive (as such things go) string of
insults about how stupid I am, how far up my ass my head is, and how
pathetic my family all the way back to Adam must be for producing such a
throwback because I''ve got no interest in adopting "the perfect
language...") at me on the merits of Python, both on group and
in-mailbox?

--
Don Bruder - da****@sonic.net <--- Preferred Email - SpamAssassinated.
Hate SPAM? See <http://www.spamassassin.org> for some seriously great info.
I will choose a path that''s clear: I will choose Free Will! - N. Peart
Fly trap info pages: <http://www.sonic.net/~dakidd/Horses/FlyTrap/index.html>

推荐答案

Don Bruder< da **** @ sonic.net>写道：


[用C / C ++重写Python程序]

Don Bruder <da****@sonic.net> writes:

[rewriting a Python program in C/C++]

像这样的C构造：

struct DictStruct
{
char * KeyArray [< somenumber>];
ValType ValArray [< somenumber>];
}

[...]同样，会是这样的：

struct DictStruct
{char Key [25];
ValType值;
DictStruct * PrevDictEntry;
DictStruct * NextDictEntry;
}

[...]最终表现得至少像Pythondict一样合理？

Something like this C construct:

struct DictStruct
{
char *KeyArray[<somenumber>];
ValType ValArray[<somenumber>];
}
[...] Similarly, would something like:

struct DictStruct
{
char Key[25];
ValType Value;
DictStruct *PrevDictEntry;
DictStruct *NextDictEntry;
}

[...] end up behaving at least reasonably like a Python "dict"?

是的。


除了它不太灵活，*多*慢，和

可能更多的马车。


Thomas

Yes.

Except that it would be less flexible, *much* slower, and
probably much more buggy.

Thomas

Don Bruder写道：

Don Bruder wrote:

一两个星期前，我在这里问过将Python移植到C.得到了一些很好的答案（注1）但现在我又得到了另一个问题ñ。实际上，更多的要求澄清一个主题，Python教程和
文档给我的理解留下了一丝阴影。

字典/字典类型...


你似乎对C感到宾至如归，你可以看看

Objects / dictobject.c和Include / dictobject。 h源代码分发。

与C / C ++或任何其他语言相比，我不关心Python有多好，坏或无关紧要。我希望这个Python代码用C / C ++编写，讨论结束。对于

A week or two ago, I asked here about porting Python to C. Got some good
answers (Note 1) but now I''ve got another question. Actually, more a
request for clarification of a topic that both the Python tutorial and
docs leave a touch murky to my understanding.

Dictionaries/"dict" types...
As you seem to feel at home with C, you could have a look into
Objects/dictobject.c and Include/dictobject.h of the source distribution.
Which part of "I don''t care how good, bad, or indifferent Python is
compared to C/C++, or any other language. I want this Python code to be
written in C/C++, end of discussion." wasn''t clear enough for those of

的人来说还不够清楚


聪明的人使用高效的工具并在现有的库上构建。如果你对主题行的C ++部分非常认真，那么标准库又名

STL有一个类似Python的字典的地图模板，可能会增强两者br />
开发和执行速度。


关闭主题（或不关闭）：

一个人可以开始讨论但不限制它，我认为这是新闻组的特色而不是烦恼。

彼得

Smart people use efficient tools and build on existing libraries. If you are
serious about the C++ part of your subject line, the Standard library aka
STL has a map template that resembles Python''s dict and might enhance both
development and execution speed.

Off topic (or not):
A single person can start a discussion but not limit it, I think that''s a
feature of newsgroups rather than an annoyance.
Peter

Don Bruder写道：

Don Bruder wrote:

一两个星期前，我在这里问到有关将Python移植到C的问题。得到了一些好的答案（注1）但现在我已经有另一个问题。实际上，更多的要求澄清一个主题，Python教程和
文档给我的理解留下了一丝阴影。

字典/字典类型...


你似乎对C感到宾至如归，你可以看看

Objects / dictobject.c和Include / dictobject。 h源代码分发。

与C / C ++或任何其他语言相比，我不关心Python有多好，坏或无关紧要。我希望这个Python代码用C / C ++编写，讨论结束。对于

A week or two ago, I asked here about porting Python to C. Got some good
answers (Note 1) but now I''ve got another question. Actually, more a
request for clarification of a topic that both the Python tutorial and
docs leave a touch murky to my understanding.

Dictionaries/"dict" types...
As you seem to feel at home with C, you could have a look into
Objects/dictobject.c and Include/dictobject.h of the source distribution.
Which part of "I don''t care how good, bad, or indifferent Python is
compared to C/C++, or any other language. I want this Python code to be
written in C/C++, end of discussion." wasn''t clear enough for those of

的人来说还不够清楚


聪明的人使用高效的工具并在现有的库上构建。

标准库（又名STL）有< map>模板可以提高开发和执行速度。


关闭主题（或不关闭）：

一个人可以开始一个讨论，但不是结束它，我认为这是新闻组的特色而不是烦恼。

彼得

Smart people use efficient tools and build on existing libraries. The
Standard library aka STL has a <map> template that might enhance both
development and execution speed.

Off topic (or not):
A single person can start a discussion but not end it, I think that''s a
feature of newsgroups rather than an annoyance.
Peter

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