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Check if a table exists in Rails
...? 'kittens'
In Rails 2, 3 & 4 the API is about tables.
# Listing of all tables and views
ActiveRecord::Base.connection.tables
# Checks for existence of kittens table/view (Kitten model)
ActiveRecord::Base.connection.table_exists? 'kittens'
Getting the status of migrations:
# Tells you all...
What's the fuss about Haskell? [closed]
...eems to love that language. Being good at Haskell seems somewhat like the hallmark of a genius programmer.
17 Answers
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How to deploy correctly when using Composer's develop / production switch?
...dependencies only while being in development, so the tools will not be installed in production (on the live server). This is (in theory) very handy for scripts that only make sense in development, like tests, fake-data-tools, debugger, etc.
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Remove not alphanumeric characters from string
...e them.
A backslash in the string needs escaping if it's to be taken literally:
"\\test\\red\\bob\\fred\\new".replace(/\W/g, '')
"testredbobfrednew" // output
Handling malformed strings
If you're not able to escape the input string correctly (why not?), or it's coming from some kind of untruste...
Parser Error Message: Could not load type 'TestMvcApplication.MvcApplication'
... +1 This was my problem too. The error message and help on this is basically non-existent. Thanks.
– Noldorin
Jan 6 '12 at 11:50
4
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Arrays, heap and stack and value types
...parts of the program and it'd clutter up the stack if they were left on it all the time. Or am I wrong? I'd guess they'd just be boxed and would live on the heap for as long the array existed.
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PostgreSQL naming conventions
.... Postgresql treats identifiers case insensitively when not quoted (it actually folds them to lowercase internally), and case sensitively when quoted; many people are not aware of this idiosyncrasy. Using always lowercase you are safe. Anyway, it's acceptable to use camelCase or PascalCase (or UPPER...
Use dynamic variable names in JavaScript
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Since ECMA-/Javascript is all about Objects and Contexts (which, are also somekind of Object), every variable is stored in a such called Variable- (or in case of a Function, Activation Object).
So if you create variables like this:
var a = 1,
b ...
How can I define an interface for an array of objects with Typescript?
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Not really an "interface for an array of objects with Typescript"
– basarat
Aug 24 '14 at 10:35
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How to run a program without an operating system?
How do you run a program all by itself without an operating system running?
Can you create assembly programs that the computer can load and run at startup, e.g. boot the computer from a flash drive and it runs the program that is on the CPU?
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