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MySQL Error 1215: Cannot add foreign key constraint
...ing to use as a foreign key are primary keys in their own tables. I have done both of these things, if I'm not mistaken. Any other help you guys could offer?
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What's the difference between io.sockets.emit and broadcast?
...ts.emit and socket.broadcast.emit? Is it only that broadcast emits to everyone BUT the socket that sends it?
3 Answers
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Javascript: best Singleton pattern [duplicate]
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"It won't if"... please, anyone still could overwrite the singleton by e.g. injecting javascript trough a bookmarklet/favlet when not using the closure pattern. It's not just about you using your own code properly, but also about avoiding malicious atta...
Best way to convert strings to symbols in hash
...my_hash.transform_keys(&:to_sym)
Using older Ruby version? Here is a one-liner that will copy the hash into a new one with the keys symbolized:
my_hash = my_hash.inject({}){|memo,(k,v)| memo[k.to_sym] = v; memo}
With Rails you can use:
my_hash.symbolize_keys
my_hash.deep_symbolize_keys
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What is a patch in git version control?
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A good answer, and one that tells me that a GIT 'patch' is not what I'm looking for.
– RonLugge
Feb 17 '12 at 18:49
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VIM Replace word with contents of paste buffer?
..., not an EX command such as :%s///g . I know that this is the typical way one replaces the word at the current cursor position: cw<text><esc> but is there a way to do this with the contents of the unnamed register as the replacement text and without overwriting the register?
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Why are side-effects modeled as monads in Haskell?
Could anyone give some pointers on why the impure computations in Haskell are modelled as monads?
8 Answers
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__getattr__ on a module
...ort time) should be no longer necessary.
In Python 3.7+, you just use the one obvious way. To customize attribute access on a module, define a __getattr__ function at the module level which should accept one argument (name of attribute), and return the computed value or raise an AttributeError:
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Draw line in UIView
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Does one not need to call CGContextBeginPath(context); before CGContextMoveToPoint(...);?
– i_am_jorf
Nov 9 '11 at 18:38
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How do I properly force a Git push?
I've set up a remote non-bare "main" repo and cloned it to my computer. I made some local changes, updated my local repository, and pushed the changes back to my remote repo. Things were fine up to that point.
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