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Renaming table in rails
...n't going to work. Instead you'll have to create an instance of the class, and call the method on the instance, like this: Class.new.method.
[EDIT]
In this instance, ActiveRecord::ConnectionAdapters::SchemaStatements isn't even a class (as pointed out by cam), which means that you can't even create...
App Inventor 2开发简单计算器 - App Inventor 2 中文网 - 清泛IT论坛，有思想、有深度
计算器这个看似简单的应用，当你一旦着手去制作时，就会发现写出来的程序漏洞百出，那些在人类看来理所当然的逻辑，对于计算机来说，却是浑然不知，一定要将每个细节都照顾到，程序才能如你所愿地运行，否则就会出现...
Global and local variables in R
I am a newbie for R, and I am quite confused with the usage of local and global variables in R.
3 Answers
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Is it expensive to use try-catch blocks even if an exception is never thrown?
...rown, it now does a relatively expensive operation of walking up the stack and seeing if any try blocks exist that would catch this exception. From a layman's perspective, try may as well be free. It's actually throwing the exception that costs you - but unless you're throwing hundreds or thousands ...
Selecting data frame rows based on partial string match in a column
...a data.table (but also remember that subsetting approaches for data.frames and data.tables are not identical):
library(data.table)
mtcars[rownames(mtcars) %like% "Merc", ]
iris[iris$Species %like% "osa", ]
If that is what you had, then perhaps you had just mixed up row and column positions for su...
gunicorn autoreload on source change
... agreed. The other answers may work, but this is by far the simplest and it's not a workaround. It's exactly what the OP wanted.
– J-bob
Aug 11 '14 at 15:08
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How do you do a ‘Pause’ with PowerShell 2.0?
...m losing it. PowerShell is annoying me. I'd like a pause dialog to appear, and it won't.
5 Answers
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How to raise a ValueError?
... ValueError instead of raise ValueError()?
– Tomasz Gandor
Sep 20 '19 at 15:14
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Purpose of #!/usr/bin/python3
...ey would start with #!/usr/bin/python3 on the first line. I don't understand why we have this.
6 Answers
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Difference between int32, int, int32_t, int8 and int8_t
... in a C program recently. I know that it stores 32 bits, but don't int and int32 do the same?
3 Answers
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