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Use of “global” keyword in Python
...l variables is seldom considered a good solution.
def bob():
me = "locally defined" # Defined only in local context
print(me)
bob()
print(me) # Asking for a global variable
The above will give you:
locally defined
Traceback (most recent call last):
File "file.py", line 9, in &l...
The shortest possible output from git log containing author and date
...ded as well.
5aed68e 17 hours ago you@me.com Shorten while loops
This is all of course in color, so it is easy to distinguish the various parts of a log line.
Also it is the default when typing git log because of the [format] section.
2014 UPDATE:
Since git now supports padding I have a nice amen...
Is there a command to refresh environment variables from the command prompt in Windows?
... environment variables with a vbs script, but you need a bat script to actually change the current environment variables, so this is a combined solution.
Create a file named resetvars.vbs containing this code, and save it on the path:
Set oShell = WScript.CreateObject("WScript.Shell")
filename =...
Run a single migration file
...just run the code directly out of the ruby file:
rails console
>> require "db/migrate/20090408054532_add_foos.rb"
>> AddFoos.up
Note: newer versions of rails may require AddFoos.new.up rather than AddFoos.up.
An alternative way (without IRB) which relies on the fact that require retu...
MySQL check if a table exists without throwing an exception
What is the best way to check if a table exists in MySQL (preferably via PDO in PHP) without throwing an exception. I do not feel like parsing the results of "SHOW TABLES LIKE" et cetera. There must be some sort of boolean query?
...
Proper way to renew distribution certificate for iOS
My distribution certificate is expiring on June 7th, along with all of my provisioning files. How do I properly renew it? Should I revoke it now and request a new one? If I do that than will all my live apps be taken down?
...
SQLite add Primary Key
... pkName ON tableName(columnName)) when DB frameworks like MS SQL's SMO actually make you add a PK after the table has been created!
– SteveCinq
Aug 31 '17 at 18:06
...
Check whether a string contains a substring
...
This way is especially preferrable, when you are searching using a variable - this way you won't have to double-escape characters (in this variable string), that are special for regular expressions (like :).
– evgeny9
...
Postfix发信的频率控制几个参数 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...tp
该语句表示postfix推迟投递所有的邮件直到执行sendmail -q命令，这样
我们就可以在ppp的脚本中加上sendmail -q，以便在拨号成功后让postfix开始投递邮件。
5． 关于延迟邮件的再投递控制
可以通过以下的几个参数实现对延迟邮件...
How to hide command output in Bash
...hat looks like this:
your_command "Is anybody listening?" >&-
Usually, output goes either to file descriptor 1 (stdout) or 2 (stderr). If you close a file descriptor, you'll have to do so for every numbered descriptor, as &> (below) is a special BASH syntax incompatible with >&am...