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When should I use Struct vs. OpenStruct?
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@IvanKolmychek: Cool, actually I prefer the block approach.
– tokland
Mar 9 '16 at 18:21
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Subscripts in plots in R
... How to load "2" from the variable? I have a loop and need to plot x_[1] x_[2] x_[3] ...
– 0x2207
Dec 11 '14 at 11:38
6
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Not equal != operator on NULL
...dicates for such situations.
This behavior is not specific to SQL Server. All standards-compliant SQL dialects work the same way.
Note: To compare if your value is not null, you use IS NOT NULL, while to compare with not null value, you use <> 'YOUR_VALUE'. I can't say if my value equals or ...
How fast is D compared to C++?
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To enable all optimizations and disable all safety checks, compile your D program with the following DMD flags:
-O -inline -release -noboundscheck
EDIT: I've tried your programs with g++, dmd and gdc. dmd does lag behind, but gdc ac...
Python: print a generator expression?
...e generator expression into a list comprehension. It's the same thing and calling list() on it. So the way to make a generator expression into a list is to put brackets around it.
Detailed explanation:
A generator expression is a "naked" for expression. Like so:
x*x for x in range(10)
Now, you ...
Is it possible to implement dynamic getters/setters in JavaScript?
...Here's a simple example that turns any property values that are strings to all caps on retrieval:
"use strict";
if (typeof Proxy == "undefined") {
throw new Error("This browser doesn't support Proxy");
}
let original = {
"foo": "bar"
};
let proxy = new Proxy(original, {
get(...
How to import module when module name has a '-' dash or hyphen in it?
...appens with sys.modules, you don't need it to import itself), just getting all of the file's globals into your own scope, you can use execfile
# contents of foo-bar.py
baz = 'quux'
>>> execfile('foo-bar.py')
>>> baz
'quux'
>>>
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PostgreSQL error 'Could not connect to server: No such file or directory'
...u are on OS X
Here is the fix:
Stop the database
cd /var
sudo rm -r pgsql_socket
sudo ln -s /tmp pgsql_socket
chown _postgres:_postgres pgsql_socket
Restart PostgreSQL (not your computer)
More information is available at "postgresql 9.0.3. on Lion Dev Preview 1".
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How can I post data as form data instead of a request payload?
In the code below, the AngularJS $http method calls the URL, and submits the xsrf object as a "Request Payload" (as described in the Chrome debugger network tab). The jQuery $.ajax method does the same call, but submits xsrf as "Form Data".
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Automatically capture output of last command into a variable using Bash?
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This is a really hacky solution, but it seems to mostly work some of the time. During testing, I noted it sometimes didn't work very well when getting a ^C on the command line, though I did tweak it a bit to behave a bit better.
This...