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Understanding repr( ) function in Python
...gt;>> x
'foo'
So the name x is attached to 'foo' string. When you call for example repr(x) the interpreter puts 'foo' instead of x and then calls repr('foo').
>>> repr(x)
"'foo'"
>>> x.__repr__()
"'foo'"
repr actually calls a magic method __repr__ of x, which gives the s...
Python loop that also accesses previous and next values
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The edited version of this is still not logically sound: At the end of the loop obj and next_ will be the same object for the last iteration, which may have unintended side effects.
– TemporalWolf
Dec 5 '17 at 22:01
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How to ALTER multiple columns at once in SQL Server
.... Each statement means a new scan but if you could alter multiple columns, all altering could have been much quicker
– erikkallen
Sep 8 '16 at 6:31
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Mercurial .hgignore for Visual Studio 2008 projects
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Here's my standard .hgignore file for use with VS2008 that was originally modified from a Git ignore file:
# Ignore file for Visual Studio 2008
# use glob syntax
syntax: glob
# Ignore Visual Studio 2008 files
*.obj
*.exe
*.pdb
*.user
*.aps
*.pch
*.vspscc
*_i.c
*_p.c
*.ncb
*.suo
*.tlb
*.tlh
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How can I do a line break (line continuation) in Python?
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Actually, you have the style guide's preference exactly backwards. Implicit continuation is preferred, explicit backslash is to be used only if necessary.
– Carl Meyer
Sep 11 '08 at 19:00
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How does Bluebird's util.toFastProperties function make an object's properties “fast”?
... eval("o" + o); // ensure no dead code elimination
}
Sans one or two small optimizations - all the below is still valid.
Let's first discuss what it does and why that's faster and then why it works.
What it does
The V8 engine uses two object representations:
Dictionary mode - in which object ar...
How does JavaScript .prototype work?
...ing languages but I've written my fair share of JavaScript code. I never really got my head around this prototype-based programming, does any one know how this works?
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Comma in C/C++ macro
...his is also a problem for square brackets and braces, even though those usually occur as balanced pairs.) You can enclose the macro argument in parentheses:
FOO((std::map<int, int>), map_var);
The problem is then that the parameter remains parenthesized inside the macro expansion, which pr...
find vs find_by vs where
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Use whichever one you feel suits your needs best.
The find method is usually used to retrieve a row by ID:
Model.find(1)
It's worth noting that find will throw an exception if the item is not found by the attribute that you supply. Use where (as described below, which will return an empty arr...
Kotlin secondary constructor
...tructors in Kotlin since these constructors are necessary sometimes, especially when working with Java frameworks and extending Java classes. Hope you'll get them back soon.
– Michael
Jul 17 '14 at 7:46
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