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Get difference between two lists
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@Drewdin: Lists do not support the "-" operand. Sets, however, do, and that what is demonstrated above if you look closely.
– Godsmith
Oct 14 '14 at 21:21
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What is polymorphism, what is it for, and how is it used?
What is polymorphism, what is it for, and how is it used?
28 Answers
28
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How do I set a variable to the output of a command in Bash?
...n to backticks `command`, command substitution can be done with $(command) or "$(command)", which I find easier to read, and allows for nesting.
OUTPUT=$(ls -1)
echo "${OUTPUT}"
MULTILINE=$(ls \
-1)
echo "${MULTILINE}"
Quoting (") does matter to preserve multi-line variable values; it is opti...
Test whether a glob has any matches in bash
If I want to check for the existence of a single file, I can test for it using test -e filename or [ -e filename ] .
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How to echo shell commands as they are executed
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set -x or set -o xtrace expands variables and prints a little + sign before the line.
set -v or set -o verbose does not expand the variables before printing.
Use set +x and set +v to turn off the above settings.
On the first line...
Algorithm to generate a crossword
Given a list of words, how would you go about arranging them into a crossword grid?
13 Answers
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How do you print in Sublime Text 2
Sublime Text 2 seems like a great editor. I just started using it a week ago in eval mode and it doesn't seem to have any printing functionality. This seems preposterous to me, but I can't find it anywhere.
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How does Access-Control-Allow-Origin header work?
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Access-Control-Allow-Origin is a CORS (Cross-Origin Resource Sharing) header.
When Site A tries to fetch content from Site B, Site B can send an Access-Control-Allow-Origin response header to tell the browser that the content of this page is ac...
No == operator found while comparing structs in C++
Comparing two instances of the following struct, I receive an error:
8 Answers
8
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ie8 var w= window.open() - “Message: Invalid argument.”
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This is an old posting but maybe still useful for someone.
I had the same error message. In the end the problem was an invalid name for the second argument, i.e., I had a line like:
window.open('/somefile.html', 'a window title', 'width=300');
The problem was 'a wi...