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Cannot overwrite model once compiled Mongoose
...an error if the model does not exist, so you can wrap it in a try/catch in order to either get the model, or create it:
let users
try {
users = mongoose.model('users')
} catch (error) {
users = mongoose.model('users', <UsersSchema...>)
}
...
Is there a builtin identity function in python?
...cin Thanks for the remark. I have added advantages/drawbacks of the two in order not to mislead anyone. And now, I really believe there should have been a builtin function that accepts any number of parameters and is a true identity :)
– rds
Jan 5 '12 at 19:14
...
jQuery validation: change default error message
... required: true,
minlength: 2,
remote: "users.php"
}
},
messages: {
firstname: "Enter your firstname",
lastname: "Enter your lastname",
username: {
required: "Enter a username",
minlength: jQuery.format("Ent...
How to determine CPU and memory consumption from inside a process?
...you will have to sample this file periodically, and calculate the diff, in order to determine the process's CPU usage over time.
Edit: remember that when you calculate your process's CPU utilization, you have to take into account 1) the number of threads in your process, and 2) the number of pro...
How to read and write into file using JavaScript?
... Also, depending on your situation you could make an ajax call to a php script and dump the data that way. This was useful in my situation where I wanted to store some data generated on the javascript side, but didn't matter how it got there.
– Dustin Graham
...
What does “abstract over” mean?
...ly.
Scala allows you to abstract over type parameters, by allowing higher-order type parameters.
Scala allows you to abstract over data access patterns, by allowing you to create extractors.
Scala allows you to abstract over "things that can be used as something else", by allowing implicit conver...
if else in a list comprehension [duplicate]
...on is in a slightly different format (think switching the subject and verb order in a sentence).
Therefore, your code [x+1 for x in l if x >= 45] does this:
for x in l:
if x >= 45:
x+1
However, this code [x+1 if x >= 45 else x+5 for x in l] does this (after rearranging the e...
Convert MySQL to SQlite [closed]
...stracts specific database differences away for you. e.g. you get these in PHP (RedBean), Python (Django's ORM layer, Storm, SqlAlchemy), Ruby on Rails (ActiveRecord), Cocoa (CoreData) etc.
i.e. you could do this:
Load data from source database using the ORM class.
Store data in memory or seriali...
Difference between Mock / Stub / Spy in Spock test framework
...her mock frameworks. In most cases when using mocks, they did not do it in order to verify behaviour (i.e. count method calls) but to isolate the subject under test from its environment. Interaction counting IMO is just an add-on goodie and should be used thoughtfully and sparingly because there is ...
What is the difference between “def” and “val” to define a function
...if you need a function (not method) for function composition or for higher order functions (like filter(even)) compiler will generate a function from your method every time you are using it as function, so performance could be slightly worse than with val.
...