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How can I check if a file exists in Perl?
...mething exists at given path using the -e file-test operator.
print "$base_path exists!\n" if -e $base_path;
However, this test is probably broader than you intend. The code above will generate output if a plain file exists at that path, but it will also fire for a directory, a named pipe, a syml...
Explain the concept of a stack frame in a nutshell
... edited Mar 9 at 8:50
virmis_007
14522 silver badges1717 bronze badges
answered Oct 18 '16 at 11:04
Aadity...
Set the location in iPhone Simulator
... where is debug menu in IOS simulator?
– Lucky_girl
Feb 6 '18 at 14:07
1
this works but it...
What characters can be used for up/down triangle (arrow without stem) for display in HTML?
...POINTING TRIANGLE
▼ - U+25BC BLACK DOWN-POINTING TRIANGLE
▴ - U+25B4 SMALL BLACK UP-POINTING TRIANGLE
▾ - U+25BE SMALL BLACK DOWN-POINTING TRIANGLE
For ▲ and ▼ use ▲ and ▼ respectively if you cannot include Unicode characters directly (use UTF-8!).
Note that the fo...
What is the difference between ng-app and data-ng-app?
...They expect non default HTML attributes to be prefaced with
data-attribute_name_here.
So, the creators of AngularJS have created alternate names for their directives that include the data- in front of them so that HTML validator programs will "like" them.
...
Get itunes link for app before submitting
...Store for your apps and company: developer.apple.com/library/ios/qa/qa1633/_index.html
– eldermao
Jun 22 '14 at 6:19
...
正则表达式 30 分钟入门教程 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...代表的含意与\d就是完全一致的：一位数字；同理[a-z0-9A-Z_]也完全等同于\w（如果只考虑英文的话）。
下面是一个更复杂的表达式：\(?0\d{2}[) -]?\d{8}。
“(”和“)”也是元字符，后面的分组节里会提到，所以在这里需要使用转义...
psql: FATAL: role “postgres” does not exist
... which will just use the latest version.
start postgres server manually: pg_ctl -D /usr/local/var/postgres start
To start server at startup
mkdir -p ~/Library/LaunchAgents
ln -sfv /usr/local/opt/postgresql/*.plist ~/Library/LaunchAgents
launchctl load ~/Library/LaunchAgents/homebrew.mxcl.post...
In Rails, how do you render JSON using a view?
...
You should be able to do something like this in your respond_to block:
respond_to do |format|
format.json
render :partial => "users/show.json"
end
which will render the template in app/views/users/_show.json.erb.
...
Add line break to 'git commit -m' from the command line
... rsy$ bash --version GNU bash, version 3.2.53(1)-release (x86_64-apple-darwin13) Copyright (C) 2007 Free Software Foundation, Inc. The output of that command is, as expected, shown in two different lines!
– ccoutinho
Jun 2 '15 at 21:49
...