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Why exactly is eval evil?
I know that Lisp and Scheme programmers usually say that eval should be avoided unless strictly necessary. I’ve seen the same recommendation for several programming languages, but I’ve not yet seen a list of clear arguments against the use of eval . Where can I find an account of the potentia...
Best way to load module/class from lib folder in Rails 3?
...
# Autoload lib/ folder including all subdirectories
config.autoload_paths += Dir["#{config.root}/lib/**/"]
Source: Rails 3 Quicktip: Autoload lib directory including all subdirectories, avoid lazy loading
Please mind that files contained in the lib folder...
What does principal end of an association means in 1:1 relationship in Entity framework
... so in your case you should use:
public class Boo
{
[Key, ForeignKey("Foo")]
public string BooId{get;set;}
public Foo Foo{get;set;}
}
Or fluent mapping
modelBuilder.Entity<Foo>()
.HasOptional(f => f.Boo)
.WithRequired(s => s.Foo);
...
Illegal mix of collations (utf8_unicode_ci,IMPLICIT) and (utf8_general_ci,IMPLICIT) for operation '=
...:
SET @rUsername = ‘aname’ COLLATE utf8_unicode_ci; -- COLLATE added
CALL updateProductUsers(@rUsername, @rProductID, @rPerm);
Option 2: add COLLATE to the WHERE clause:
CREATE PROCEDURE updateProductUsers(
IN rUsername VARCHAR(24),
IN rProductID INT UNSIGNED,
IN rPerm VARCHAR(16...
How would you make a comma-separated string from a list of strings?
...
",".join(l) will not work for all cases. I'd suggest using the csv module with StringIO
import StringIO
import csv
l = ['list','of','["""crazy"quotes"and\'',123,'other things']
line = StringIO.StringIO()
writer = csv.writer(line)
writer.writerow(l)
csv...
'UserControl' constructor with parameters in C#
Call me crazy, but I'm the type of guy that likes constructors with parameters (if needed), as opposed to a constructor with no parameters followed by setting properties. My thought process: if the properties are required to actually construct the object, they should go in the constructor. I get two...
what is the best way to convert a json formatted key value pair to ruby hash with symbol as key?
... string key
}
}
Method 1: JSON.parse - symbolizes all keys recursively => Does not preserve original mix
JSON.parse( h.to_json, {:symbolize_names => true} )
=> { :youtube => { :search=> "daffy", :history => ["goofy", "mickey"] } }
Method 2: ActiveSup...
How to use a switch case 'or' in PHP
...ase 2:
echo "the value is either 1 or 2.";
break;
}
This is called "falling through" the case block. The term exists in most languages implementing a switch statement.
share
|
improve ...
Java Class.cast() vs. cast operator
...ject) isn't special to the compiler. It could be optimized when used statically (i.e. Foo.class.cast(o) rather than cls.cast(o)) but I've never seen anybody using it - which makes the effort of building this optimization into the compiler somewhat worthless.
...
What's the difference between `on` and `live` or `bind`?
.../ Equivalent `on`
$(document.body).on("click", ".mySelector", fn);
Internally, jQuery maps all these methods and shorthand event handler setters to the on() method, further indicating that you should ignore these methods from now on and just use on:
bind: function( types, data, fn ) {
return...