附加到不存在的列表 [英] append to non-existing list
问题描述
您好,
如果我这样做:
for sqlsth中的行:
________ pkcolumns.append (row [0] .strip())
________etc
没有事先的
:
pkcolumns = [];
我在第一次迭代时遇到这个错误:
UnboundLocalError:在分配之前引用的局部变量''pkcolums'
我猜那个'这是正常的,因为它是python的工作方式......?!?
我的问题是:是否无法附加到不存在的列表中?
我懒得首先宣布它,恕我直言它臃肿的代码,并且(不要知道,如果在这里说的话,我会知道)来自(php)我用过
不需要它...
问候,
Yves
您好
我认为没有办法追加到现有的清单。
>
对我的问题感到抱歉,但英语是我的第二语言d我
我不知道IHMO(或恕我直言)的含义是什么。我用Google搜索并发现
,这意味着在我的谦卑的意见中,这是真的吗?谢谢并接受
我的抱怨并不是完全谈论你的问题。
Daniel
我担心你要么回到php或者其他任何编程
语言,以适应你的风格或改变你的风格以适应python。
有很多我不喜欢python但如果你必须使用它,你需要b
$ b必须应对它。
Yves Glodt写道:我的问题是:有没有办法追加到不存在的列表?
我懒得首先声明它,恕我直言它臃肿的代码,并且(不要我知道在这里说是不是很好我来自哪里(php)我用过
不需要它...
问候,Yves
Yves Glodt写道:你好,
>如果我这样做:
对于sqlsth中的行:
________ pkcolumns.append(row [0] .s行程())
________ iec
没有事先的
:
pkcolumns = [];
我在第一次迭代时收到此错误:
UnboundLocalError:在赋值之前引用局部变量''pkcolums'
我想这是正常的,因为它是python的工作方式......?!?
我的问题是:有没有办法追加到现有的清单?
我懒得先申报它,恕我直言,它会使代码膨胀,而且(不要)知道我这里说的好吗(我)来自哪里(php)我用过
不需要它......
问候,
Yves
你的意思是你要输入pkcolumns只有一次保持你的代码简短?
这样的东西会有用吗?
pkcolumns = [row.strip()for sqlsth中的行]
Hello,
if I do this:
for row in sqlsth:
________pkcolumns.append(row[0].strip())
________etc
without a prior:
pkcolumns = [];
I get this error on first iteration:
UnboundLocalError: local variable ''pkcolums'' referenced before assignment
I guess that''s normal as it''s the way python works...?!?
My question is: Is there no way to append to a non existing list?
I am lazy for declaring it first, IMHO it bloats the code, and (don''t
know if it''s good to say that here) where I come from (php) I was used
to not-needing it...
regards,
Yves
Hi
I think there''s no way to append to a non existing list.
Sorry about my question, but the English is my second language, and I
don''t know what is the meaning of IHMO (or IMHO). I googled and found
that it means "In My Humbled Opinion", is that true? Thanks and accept
my appologies for not talking entirely about your problem.
Daniel
I am afraid you have to either go back to php or whatever programming
language that fits your style or change your style to fit python.
There is a lot I don''t like about python but if you have to use it, you
have to cope with it.
Yves Glodt wrote:My question is: Is there no way to append to a non existing list?
I am lazy for declaring it first, IMHO it bloats the code, and (don''t
know if it''s good to say that here) where I come from (php) I was used
to not-needing it...
regards,
Yves
Yves Glodt wrote:Hello,
if I do this:
for row in sqlsth:
________pkcolumns.append(row[0].strip())
________etc
without a prior:
pkcolumns = [];
I get this error on first iteration:
UnboundLocalError: local variable ''pkcolums'' referenced before assignment
I guess that''s normal as it''s the way python works...?!?
My question is: Is there no way to append to a non existing list?
I am lazy for declaring it first, IMHO it bloats the code, and (don''t
know if it''s good to say that here) where I come from (php) I was used
to not-needing it...
regards,
Yves
You mean you want to type "pkcolumns" only once to keep your code short?
Would something like this be useful?
pkcolumns = [row.strip() for row in sqlsth]
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