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The type 'string' must be a non-nullable type in order to use it as parameter T in the generic type
...simplify your code by using auto-implemented properties:
public class WordAndMeaning
{
public string Word { get; set; }
public string Meaning { get; set; }
}
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Heroku “psql: FATAL: remaining connection slots are reserved for non-replication superuser connectio
...t this error message when trying to access the database, both from the CLI and from loading a page on the server:
4 Answers...
What do the return values of node.js process.memoryUsage() stand for?
...
In order to answer this question, one has to understand V8’s Memory Scheme first.
A running program is always represented through some space allocated in memory. This space is called Resident Set. V8 uses a scheme similar to the Java Virtual Machine and divides the memory i...
Using :before CSS pseudo element to add image to modal
...class Modal which is absolutely positioned, z-indexed above it's parent, and nicely positioned with JQuery. I want to add a caret image (^) to the top of the modal box and was looking at using the :before CSS pseudo selector to do this cleanly.
...
Is it possible to use global variables in Rust?
...t spawn. The upside is that unlike truly global state, it is entirely safe and is not a pain to use - true global state is a massive pain in any language. Here's an example:
extern mod sqlite;
use std::cell::RefCell;
thread_local!(static ODB: RefCell<sqlite::database::Database> = RefCell::n...
Difference between dispatch_async and dispatch_sync on serial queue?
...k is finished whereas dispatch_async return after it is added to the queue and may not finished.
for this code
dispatch_async(_serialQueue, ^{ printf("1"); });
printf("2");
dispatch_async(_serialQueue, ^{ printf("3"); });
printf("4");
It may print 2413 or 2143 or 1234 but 1 always before 3
for ...
Why use @PostConstruct?
...s are injected. In the @PostConstruct method the bean is fully initialized and you can use the dependencies.
because this is the contract that guarantees that this method will be invoked only once in the bean lifecycle. It may happen (though unlikely) that a bean is instantiated multiple times by th...
Set Colorbar Range in matplotlib
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Using vmin and vmax forces the range for the colors. Here's an example:
import matplotlib as m
import matplotlib.pyplot as plt
import numpy as np
cdict = {
'red' : ( (0.0, 0.25, .25), (0.02, .59, .59), (1., 1., 1.)),
'green':...
What specifically are wall-clock-time, user-cpu-time, and system-cpu-time in UNIX?
...ed on the names, but what specifically are wall-clock-time, user-cpu-time, and system-cpu-time in UNIX?
4 Answers
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Set value to null in WPF binding
...le:
<TextBox Text="{Binding Price, TargetNullValue=''}"/>
Which stands for (thanks Gregor for your comment):
<TextBox Text="{Binding Price, TargetNullValue={x:Static sys:String.Empty}}"/>
sys is the imported xml namespace for System in mscorlib:
xmlns:sys="clr-namespace:System;ass...