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cannot convert data (type interface {}) to type string: need type assertion
...]i to its value type, we have to do it individually:
// var items []i
for _, item := range items {
value, ok := item.(T)
dosomethingWith(value)
}
Performance
As for performance, it can be slower than direct access to the actual value as show in this stackoverflow answer.
...
Why is \r a newline for Vim?
...
From http://vim.wikia.com/wiki/Search_and_replace :
When Searching
...
\n is newline, \r is CR (carriage return = Ctrl-M = ^M)
When Replacing
...
\r is newline, \n is a null byte (0x00).
...
What are the options for storing hierarchical data in a relational database? [closed]
...st.
+-------------+----------------------+--------+-----+-----+
| category_id | name | parent | lft | rgt |
+-------------+----------------------+--------+-----+-----+
| 1 | ELECTRONICS | NULL | 1 | 20 |
| 2 | TELEVISIONS | 1 | 2 | ...
String comparison in Python: is vs. == [duplicate]
...ython allows anything to be used as a boolean expression. If you have bool_a == 3 and bool_b == 4, then bool_a != bool_b, but bool_a xor bool_b is false (because both terms are true).
– dan04
Jun 7 '10 at 12:57
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How do you remove a Cookie in a Java Servlet
... seems to work consistently across all browsers.
– ug_
Oct 27 '13 at 9:29
5
I'm not sure you shou...
Cannot install packages using node package manager in Ubuntu
...e node
sudo apt-get remove nodejs
curl -sL https://deb.nodesource.com/setup_8.x | sudo -E bash -
sudo apt-get install -y nodejs
sudo ln -s /usr/bin/nodejs /usr/bin/node
alias node=nodejs
rm -r /usr/local/lib/python2.7/dist-packages/localstack/node_modules
npm install -g npm@latest || sudo npm instal...
Multiple inheritance for an anonymous class
...ited Jun 5 '14 at 14:45
aspiring_sarge
1,84711 gold badge2222 silver badges3232 bronze badges
answered May 1 '11 at 13:04
...
How to install a gem or update RubyGems if it fails with a permissions error
... which gem >/dev/null; then PATH="$(ruby -rubygems -e 'puts Gem.user_dir')/bin:$PATH" fi <br>Source:guides.rubygems.org/faqs/#user-install
– Inder Kumar Rathore
Aug 22 '17 at 10:42
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How to convert R Markdown to PDF?
...ying an output format to the rend function. E.g.,
render("input.Rmd", "pdf_document")
Command-line:
When I run render from the command-line (e.g., using a makefile), I sometimes have issues with pandoc not being found. Presumably, it is not on the search path.
The following answer explains how to...
Comparing Dates in Oracle SQL
...u should transform your string into a date. Either by using the built-in TO_DATE() function, or a date literal.
TO_DATE()
select employee_id
from employee
where employee_date_hired > to_date('31-DEC-95','DD-MON-YY')
This method has a few unnecessary pitfalls
As a_horse_with_no_name noted...